Two Recent Finds from the Corinthia

The Googlebots are proving less reliable than they once were. Here are two news stories from the last week or so that I just learned about via FB. These should be of obvious interest to Roman history and archaeology folk.

First, another Roman chamber tomb has been found in Corinth. This tomb, like the Roman tomb found last year, comes from the plain north of the urban center which was always a principal area of burial for the Greek and Roman cities of Corinth.  Initial reports evidently suggest a slightly earlier date (1st-2nd AD or earlier) than the 3rd century tomb discovered last year. An excerpt from the article (“Roman chamber tomb found in Ancient Corinth”, Nov. 14, 2013) via the Archaeology News Network:

Measuring 3.30m by 2.63m., the tomb has been initially dated to between the 1st and 2nd centuries AD, but may be earlier. It was entered from the south through a staircase decorated on either side with two ceramic tiles in deep relief, one showing a quadriga (four-horse chariot), and the other depicting a chariot pulled by dolphins next to a sea creature.  Inside, there were vaults over niches where ash urns were placed, and three larnaces (terracotta coffins) containing bones, oil lamps, bronze coins and pottery shards. One of the coffins was painted to depict bed covers. The interior of the tomb also contained very well-preserved wall paintings, depicting garlants, fruit and three figures, two men and a woman.

The second news piece from the Greek Report is the discovery of an “Ancient Roman Villa and SPA Discovered by Archaeologists in Greece” (Nov. 12, 2013) near the neighborhood known as Katounistra in Loutraki on the western side of the Isthmus. Not sure where this is and what relation it has to another important Late Roman villa excavated by the Greek Archaeological Service in Katounistra in the 1990s.

Maps of the Corinthia

I have updated the Maps section of this website as well as the subdirectories for Contours and Maps of the Corinthia. The latter contains a gallery of maps generated for free distribution for educational and research purposes. The maps present the Corinthia at different scales, with 20 meter and 100 meter contours, generated from the SRTM DEM. Some examples of the gallery maps include….

A simple base map of the Corinthia which can be modified through a photo editing program to add sites, roads, and the like:

CM_Corinthia_7_20m

A map displaying the most important ancient sites in the Corinthia from the Archaic-Late Roman period:

CM_Corinthia_1_100m

A map of the Isthmus with sites discussed by Pausanias in the mid-2nd century AD:

CM_Corinthia_5_100m

A partial gazetteer of ancient and modern sites and settlements in the region:

CM_Corinthia_3_20m

These maps are intentionally basic—no stream valleys, roads, canals, or fortification walls. Feel free to add and modify to your own ends. Please contact me for adopting these maps for the purposes of publication.

Contours of Greece from SRTM Data

This post for users of GIS.

You should really take the time to learn how to create contour lines automatically so that you can produce topographic maps at different elevation intervals for whatever region you are researching.

But, for those without access to extensions like spatial analyst that enable the conversion, or the time to mess with this, I will offer the following shape file data sets for 1) the Peloponnese and part of central Greece, and 2) the Corinthia.

The two images below display the extent of the contours that I’m linking to here.

The first shows  the extent of contour coverage for southern and central Greece. At the end of this post, you’ll see links for 20 meter and 100 meter contours for this broad area.

Peloponnese_SRTM_100m

The second image shows the modern regional unit of the Corinthia (and western Attica), which includes the ancient territories of Corinth, Sikyon, Tenea, and Megara. I will link to files containing 20 meter contours for this area.

Corinthia_20m_SRTM

I generated these shape files from SRTM data through a simple conversion via the “Contour” tool in the ArcGIS extension Spatial Analyst — see my previous post about the process. (SRTM data refers to Shuttle Radar Topography Mission that marks a particular research endeavor by NASA to make high-resolution topographic data globally available.)

The image below shows the SRTM DEM that was used to generate the contours.

SRTM_41_05

I downloaded the SRTM file shown above (“SRTM_41_05”) from the CGIAR Consortium for Spatial Information website, which describes the data sets in the following way:

“The CGIAR-CSI GeoPortal is able to provide SRTM 90m Digital Elevation Data for the entire world. The SRTM digital elevation data, produced by NASA originally, is a major breakthrough in digital mapping of the world, and provides a major advance in the accessibility of high quality elevation data for large portions of the tropics and other areas of the developing world. The SRTM digital elevation data provided on this site has been processed to fill data voids, and to facilitate it’s ease of use by a wide group of potential users. This data is provided in an effort to promote the use of geospatial science and applications for sustainable development and resource conservation in the developing world. Digital elevation models (DEM) for the entire globe, covering all of the countries of the world, are available for download on this site. The SRTM 90m DEM’s have a resolution of 90m at the equator, and are provided in mosaiced 5 deg x 5 deg tiles for easy download and use. All are produced from a seamless dataset to allow easy mosaicing……

Dr. Andy Jarvis and Edward Guevara of the CIAT Agroecosystems Resilience project, Dr. Hannes Isaak Reuter (JRC-IES-LMNH) and Dr. Andy Nelson (JRC-IES-GEM) have further processed the original DEMs to fill in these no-data voids. This involved the production of vector contours and points, and the re-interpolation of these derived contours back into a raster DEM. These interpolated DEM values are then used to fill in the original no-data holes within the SRTM data. These processes were implemented using Arc/Info and an AML script. The DEM files have been mosaiced into a seamless near-global coverage (up to 60 degrees north and south), and are available for download as 5 degree x 5 degree tiles, in geographic coordinate system – WGS84 datum.”

According to their disclaimer about liability, distribution, and acknowledgement/citation, these contours are freely available for (non-commercial) educational and research purposes, but users should cite the data source for publications and reports:

“DISTRIBUTION

Users are  prohibited from  any commercial,  non-free resale,  or redistribution without explicit written permission from CIAT. Users should acknowledge CIAT  as the source used  in the creation  of any reports,  publications, new data  sets, derived products, or services resulting from the use of this data set. CIAT also request  reprints of  any publications  and notification  of any  redistributing efforts. For commercial  access to  the data,  send requests  to Andy Jarvis.

ACKNOWLEDGMENT AND CITATION

We kindly ask  any users to  cite this data  in any published  material produced using this data,  and if possible  link web pages  to the CIAT-CSI  SRTM website (http://srtm.csi.cgiar.org).

Citations should be made as follows: Jarvis A., H.I. Reuter, A.  Nelson, E. Guevara, 2008, Hole-filled  seamless SRTM data V4, International  Centre for Tropical  Agriculture (CIAT), available  from
http://srtm.csi.cgiar.org.”

DATA SETS

Finally, the data sets. The following zipped folders each contain 7 individual files that are needed as a package for recognition by ArcGIS. Right click on the file and save to your computer. I will post some ‘permanent’ version of the notes above to this page in the website.

Enjoy, but please do remember to cite the CIAT-CSI  SRTM website.

A Better Way to Make Topopographic Maps

When I attended the THATCamp Philly in September 2011, I listened to a presentation by Dianne Dietrich about the value of programming for teachers and researchers in the humanities: the goal is to avoid processes that can be done automatically. If you have to repeat a step more than 3 times, she said, you should look for an automative process. I’ll admit that I was a little lost in the ensuing discussion about programming basics and in the subsequent session about XML, nor was I was the only one—the dean of humanities at my college, Peter Powers, caused a twitter storm when he later admitted that the THATCamp experience was somewhat inaccessible (and would be for many humanities faculty). One thing I took away from the conference, however, was that it would be a good idea some day soon to take a basic programming class and that I should be on the lookout for automative processes that save time. My work with Zotero this fall confirmed that conclusion. Creating a massive digital library of ancient texts (which I’ll write about soon) would certainly benefit from knowledge of basic programming.

Enter GIS and topographic world (and GIS experts will no doubt laugh at my folly here). If you’ve followed this website, you may recall my post last spring about the progress we were making in creating higher-resolution topographic layers for the Corinthia. Over the last couple of years, I have been slowly chipping away at 20 meter contours for the region based on the Greek 1:50,000 topographic maps. Digitizing a topographic map of the Corinthia in this manner is an extremely slow process as you follow contour lines of the map with your mouse and click click click along them to trace a digital copy – note the red “digitized” lines in the image below and the squiggly contour lines in gray /black that are not digitized.

January 2012 102

A handful of students at Messiah College had made slow progress on the topographic map over the last couple of years with this tracing method. The students benefited from getting to work with ArcGIS and we worked slowly toward completion of a worthwhile project. After dozens of hours of work, we had finished the Isthmus, the western plain, and the central Corinthia and had left only the territory east of the canal.

When I commented on our progress last March, Richard Rothaus of Trefoil Cultural and Environmental posted a link to this 2006 article by Konstantinos G. Nikolakopoulos and Nektarios Chrysoulakis about the accuracy of the Greek 1to50:000 topographic maps. The authors compare topographic maps digitized from the Greek 1to50k maps (which were created in the 1980s from aerial photographs), to topographic maps generated from two sets of NASA space imagery and digital elevation models, ASTER and SRTM. They conclude that the topographic data from ASTER and SRTM is more accurate and can be used to correct the Hellenic 1to50k maps: “The accuracy of the ASTER DEM is considered as suitable for updating 1:50.000 topographic maps and the SRTM DEM is suitable for the detection of areas that need updating.”

Sounded valuable, but I had done all this work already using the Greek topo maps as the base, and I figured it would be easier for me to complete the process of tracing the old-fashioned way than take the time to learn how to create contour lines from DEMs. So, in late October, I decided I would finish the map the traditional way by tracing and clicking. I focused on the Perachora peninsula as an experiment to determine how long it would take to complete the entire Corinthia. The image below shows much I had accomplished after 2 hours: note the red lines marking the digital copy over the mass of gray contour lines. So I had probably digitized 10-15% of the peninsula. I reckoned that finishing the contours for all of the Corinthia would have taken 40-60 hours or more. 

Perachora-peninsula-digitized

Clearly that was not a good use of my time, so I explored the alternate option, creating topographic maps from NASA DEMs. I began by downloading the DEM model from this SRTM website, and later, the ASTER files from Earth Explorer. Once I added these into ArcGIS, it was a pretty easy process to learn the steps in ArcGIS, as this youtube video shows (and many other online tutorials). I did encounter a few ‘rookie’ problems like not having the necessary ArcGIS extensions and getting the DEM rasters to relate to the rest of my data, but these were easily resolved by talking to friends. The entire learning exercise required only a long day, and the conversion itself takes about 45 seconds! In less than a minute, I have contours for all of the Corinthia.

Corinthia_Master

The brilliant thing is that I can reduplicate the process to create contours at 1 meter, 5 meter, 100 meter, 500 meter intervals for all of the Corinthia, or for that matter, all of Greece. As I learned in subsequently corresponding with Angela Ziskowski and Dan Lamp, these contours can be exported to AutoCad in DWG format.

A major surprise was how closely the topographic data from the DEMs aligned with the 1to50k Greek maps. In the image below, compare the red lines with blue labels showing the contours created from the ASTER image with the underlying black lines with black labels showing the contours of the Greek 1to50s. They almost always fall within 10-20 m of the Greek army maps and frequently overlay exactly—and remember that it is the Greek army maps that are less accurate here.

ASTER-Hellenic_Compared

In the next week, I’ll post links to 20 meter contours for Greece for free download, and also updated maps of the Corinthia. Thanks to Brandon Olson, Bill Caraher, and Richard Rothaus for helping me figure all of this out.

Another look at Land of Sikyon

One spring day in 2005, I ran into Yannis Lolos at the Blegen Library in Athens carrying around his recently completed monograph on the history and archaeology of the region of Sikyon, the polis immediately west of Corinth. He told me at the time that the hundreds and hundreds of freshly printed pages in his hands, destined for the publication desk of the American School of Classical Studies at Athens, had required a tremendous amount of work. Now that I’ve seen the final product, Land of Sikyon: Archaeology and History of a Greek City-State (Princeton 2011), I can see he wasn’t exaggerating. This is truly a magnum opus representing a massive undertaking that could only have required thousands of hours of work. I spent a couple of days last week working through the volume, but I felt like one only scratching the surface—much like Caraher’s cat attacking a sofa

The most impressive aspect of Land of Sikyon is its comprehensiveness. Lolos has produced the first topographic study of the entire region of Sikyonia (360 km) from prehistory to the Early Modern period. He mines and discusses all relevant ancient and medieval texts and early modern literature, summarizes relevant excavation finds, and presents page after page of original observation and interpretation of the finds from his reconnaissance survey of the territory. While he claims in places that his work is not the final say for the history of the region but only a new beginning, it is most certainly comprehensive in its regional framework, diachronic perspective, and attention to a wide range of evidence. One might compare it to James Wiseman’s The Land of the Ancient Corinthians, but double the word count and twice the number of photos, maps, plans, and tables. At 635 pages, it rivals in size any regional survey volume, but, unlike most survey volumes, Land of Sikyon was authored (almost) entirely by one person.

This outline and structure of the book shows Lolos’ thematic breaks, which, as he notes in the intro, correspond to the stages of his research (For a descriptive summary, see Bill Caraher’s BMCR review):

Introduction (pp. 1-6)

Ch. 1. Physical Environment and Resources (pp. 7-58): topography; boundaries and resources of ancient polis, land use in the premodern era

Ch. 2. Sikyonia from Prehistoric Times to the Ottoman Era (pp. 59-92): a history of the region based mainly on textual evidence

Ch. 3. Land Communications (pp. 93-180): a reconstruction of the road network of the territory based on Lolos’ topographical survey (1996-1998 )

Ch. 4. Defenses (pp. 181-268): discussion of the region’s fortifications based on topographical survey in 1996-1998 (forts, guard houses, patrol houses)

Ch. 5. Settlements: The City and its Countryside (269-376): diachronic reconstruction of settlement system based on extensive survey in 2000-2002

Ch. 6. Sacra Sicyonia (pp. 377-414): sacred landscapes based on survey, excavation, and textual evidence

Ch. 7. Conclusion (pp. 415-418)

There follows seven appendixes. The most detailed and extensive covers the register of sites (pp. 419-548), while there are also chapters by Lolos on aqueducts, public land, and a building inscription, and chapters from his colleagues on the Cave of Lechova, roof tiles, and an inscribed sherd. Six neat maps show political boundaries, topography, rivers and streams, fault lines, geological strata, vegetation patterns, modern settlements and toponyms, archaeological sites, ancient roads of the Sikyonia and the western Korinthia, and the features and sites of the Ancient Sikyon plateau. These are freely available for downloading as PDF files via their DOI names (listed at the end of the book).

The structure of the work reveals Lolos’ principal interests. The introduction and the first two chapters establish the context for understanding Sikyonia’s history, while the subsequent chapters of the monograph (3-6) detail the results of the topographical survey and the extensive pedestrian survey.  For the general reader interested broadly in the history and archaeology of the northeast Peloponnese but with no knowledge of Sikyon per se, chapters 1 and 2 could be the most useful in the volume. The first discusses agriculture and the natural resources of Sikyonia while the second provides a summary of Sikyon’s political and cultural history over four millennia. Both highlight how Sikyon’s and Corinth’s history were entangled in many different ways —by natural resources (e.g., the famous coastal plain between Corinth and Sikyon, the flora and crops of the regions) and parallel political developments (neighboring poleis in the Archaic-Hellenistic periods, complex interactions with external powers in the Hellenistic period). From the Roman period to the early modern era, Sikyon’s history, in fact, was directly overshadowed by the megalopolis Corinth. Indeed, the selection of Carl Rottmann’s oil painting, Sikyon-Corinth (1836-1838), for the cover of the book, draws attention to this theme of Sikyon’s relationship and interaction with neighboring Corinth, its acropolis visible in the distance.

CarlRottmann_Sikyon-Corinth

Chapters 3-5 are without question the heart of the monograph, each numbering 80-100+ pages. These do not make for light or easy reading but require attention to Lolos’ topographic arguments (based on the maps at the end of the volume), archaeological arguments (based on references to scattered remains of roads, fortifications, and settlements), and textual arguments about the interpretation of ancient literature and early modern sources. The general reader can gain a quick overview of Lolos’ arguments through the useful summaries at the end of each chapter, but will still benefit from dipping into particular sections of interest and examining the images, figures, and tables (cf., for example, the walking distances and travel times from Corinth in Table 3.1). The scholar of the northeast Peloponnese will want to spend some time wading through Lolos’ arguments. For example, the author reconstructs an extensive road network across the Sikyonia from wheel ruts (most of which, he argues, are deliberately cut), natural corridors, road bed cuttings, historical sources, bridge locations, and graves, and argues that almost all of these roads originated in antiquity, primarily the era of the polis. The connection between these scattered bits is necessarily speculative as most of these features are not especially diagnostic, but the author’s arguments are still compelling. I found convincing his argument (pp. 98-110) for the existence of a Roman road across the coastal plain connecting the regions of Corinth and Sikyon, especially as it corresponds to modern village locations and lines up nicely with David Romano’s observations about an artery that structured the Roman centuriation of the Corinth’s western territory. Lolos’ arguments about the functions of rural towers and fortifications in the territory—mostly for the defense of the polis, mostly guarding interstate roads—are balanced, coherent, and defensible.

I was less convinced by Lolos’ reconstruction of settlement patterns (Ch. 5), based on his extensive survey of the territory.  While the discussion is nuanced and sensible, recognizing (p. 272) the major methodological differences between extensive survey and intensive survey, he nonetheless attempts to reconstruct demographic patterns on the basis of relative changes in the number of sites identified for each period. So, for example, he sees a mostly empty Geometric countryside (9 sites), a surprisingly sparse Archaic period (26 sites), a spike in the Classical era (45 sites), a decline in the Hellenistic (22 sites) to Early-Middle Roman (34 sites), and a spike in the Late Roman period (61 sites), etc..—archaeological patterns that seem out of sync with the picture from textual sources (e.g., the early Hellenistic period is a bright phase in Sikyon’s history under Aratus). Whether or not these could reflect true demographic change or the changing demographic relationship of town and country, as Lolos ponders, I found two main weaknesses in his assessment of the pattern.

First, Lolos’ survey was not intensive, and therefore not likely to detect the smaller farmsteads, tenant residences, and seasonal habitations that must have been common throughout Sikyon’s history. The investigator followed the kapheneion method: his research began at the village cafes and pursued local knowledge of farmers and inhabitants.  This method was a certain path to locating sites but also led him inevitably to examine the most visible sites of the territory. By my count, 94 of the 148 habitation sites listed in the catalogue are associated with structures or architectural fragments like cut stone, rubble, and ashlar blocks; only 1/3 of the sites in the volume were identified from pottery scatters alone. There can only be an enormous corpus of unidentified smaller sites in the Sikyonia that escaped detection from Lolos’ survey. When Lolos completes an intensive survey of a sample of the territory, we will have a much better sense of the range of settlements in the region. But until he does so, his results based on extensive survey cannot be reliably compared with that of intensive survey projects. 

Lolos, of course, recognizes the important methodological difference between extensive and intensive survey (p. 272) in this work as well as in his decision to undertake a high-resolution urban survey of the Sikyon plateau, but maintains that the chronological layers documented in his extensive survey are still meaningful relative to one another.  In recent years, I have come to doubt our ability to reconstruct demographic changes from simple changes in the quantity of “sites” of different periods.  As several of us have argued from the Eastern Korinthia Survey data (here, here, and here), knowledge of ceramic periods is always differential: the Late Roman period, for instance, has much greater visibility than the Hellenistic or Early Roman because of its more identifiable coarse ware body sherds with their characteristic combed and grooved surface treatments. One cannot reliably assess change in rural settlement without also assessing the degree to which successive periods within a region are differently visible during survey. While Lolos acknowledges these issues and also notes some of the artifacts identified at each site, he does not give the reader enough information about the artifacts to determine whether the patterns are really a product of changes in deposition of artifacts over time, or simply a result of the biases of identification. I left this chapter wondering whether the 61 Late Roman sites were really an indication of “the return of the population to the countryside” (p. 367), or just a result of greater visibility in diagnostic tiles and “hundreds of ribbed body sherds” (p. 366). I also wondered whether 22 Hellenistic sites and 34 Early Roman-Middle Roman sites were really much less than 45 Classical sites. In some regions of Greece and the Aegean, after all, changes between these periods have been much more drastic. Could not one put a more positive spin (e.g., settlement continuity) on these patterns? 

These sorts of methodological questions can best be answered in subsequent phases of intensive survey which Lolos plans to undertake eventually in the territory (p.272). They do not detract from this volume’s major accomplishment, which is to move the history and archaeology of Sikyon from political history of the urban center to the broader framework of territory and landscape.

 

Further Reading:

Maps of the Corinthia

Maps of the Corinthia are surprisingly rare via the internet, let alone maps of the ancient Corinthia. A google image search on “Korinthia” or “Corinthia” turns up two dozen very coarse road maps of the northeastern Peloponnese mainly produced or posted by tourist agencies.

I have added a new section of this website, Maps of the Corinthia, where I have posted some higher resolution maps of the Isthmus and Corinthia, the course of the diolkos, the Eastern Korinthia Survey, and a gazetteer of archaeological sites.  This area will grow as I continue the digital work and if you would like to donate anything to the cause, I’d be glad to post it there.  You are free to use these maps for the purposes of education and scholarly presentation, but not publication except by request.

I have produced the maps posted on that page, but have made use of some of the GIS data entered as part of the Eastern Korinthia Archaeological Survey (1998-2002).  Richard Rothaus, especially, and his Archaeological Computing Laboratory at St. Cloud State University, conducted an enormous amount of work in the late 1990s in digitizing the Eastern Corinthia from 1:5,000 maps.  They did it all manually via digitizing tablets (tracing the physical map itself), not via the heads-up digitizing (tracing an image on the computer screen) we use today.

The Archaeological Computing Laboratory completed a ginormous labor of GIS: faults, streams, boundaries, settlements, topo lines, survey units, etc.. The elevation data alone is impressive: some 8,426 separate contour lines, and these are 2-meter contour lines, each requiring hundreds of clicks of the mouse.  click..click..click.

To show you one example, the following image displays the Eastern Corinthia with a dark mass of lines, the aggregate of the 2 meter contours.  The red line follows one reconstruction (Salmon 1984) of the boundary of the classical Corinthia.

If we zoom in to the mountainous SE Corinthia, you can get a sense of the detail:

And the detail….

8,426 lines. Since my main project is the Isthmus, consider the problem I encounter with the following image, which shows the archaeological sites of the Corinthia against its high resolution topographic background.

Note where those topo lines stop.  I am currently working on adding at least the topo data (20 m contours) from the other side of the Isthmus.  But in the interest of time, I’ll be working from maps of larger scale, 1 to 50:000 rather than the 1:5000s.

Watch for updates and maps as I make progress on this.

Friday Photo Gallery – Views from Acrocorinth

I recently received a request by email for some high-resolution images of the Corinthia.  I have taken about 5,000 photos of the Corinthia over the last several years and will be uploading some of my digital image collection to the photo gallery section of this website.  I’ll start with some of the views of the Corinthia from the peak of Acrocorinth and the road up.  Feel free to use them for personal and educational  purposes, but contact me about permission for publication or commercial use.

Another view of Corinth's western coastal plain from Acrocorinth