Historical and Archaeological Background



The focus of the AROURA survey is the fertile plain surrounding the site known today as Glas (Γλας), a fortress built on a natural rock outcropping, dating to the last phases of the Greek Bronze Age -- the Late Helladic (LH) IIIB (or "Mycenaean") Period. Glas sits in the northeast quarter of the Kopaic Basin, or Kopaïs, in the modern prefecture of Viotía (Classical Boiotia), central mainland Greece. The Basin comprises a plain of some 350 square kilometers within a territory of soluble carbonate bedrock, specifically Jurassic, Cretaceous, and Paleogene (c. 200-23 m.y.a.) limestones and Neogene (c. 23-2.5 m.y.a.) flysches. Geologically recent, Quaternary (2.5 m.y.a. - present) alluvial sediments have accumulated in a rift (graben) in the surrounding carbonate formations. It is thus a landform known technically as a karst polje. Significant for archaeology, karstic sinkholes -- Greek katavóthres (singular katavóthra / καταβόθρα) -- exist at the edge of the Kopaïs, particularly to the north and east, where the plain meets the upthrust limestone. Since the end of the last ice age (c. 12,000 y.a.), the Basin has encompassed a shallow lake, whose wetland margins have fluctuated with the seasons, as well as with larger climatic cycles. Several rivers -- chief among them the Melas, Kephissos, Herkyna, and Phalaros -- flowing from mountains to the west, have fed this lake.

Humans have made at least four attempts to claim land from the Kopaic wetlands (mainly for agriculture), only two of which are known to have been successful. The first was completed in the thirteenth century BCE, when the fortress of Glas was built, and the second was completed in the twentieth century CE. These have variously involved channeling major rivers, drainage canals, dikes, and improvement of the natural katavóthres. There are already several kinds of strong circumstantial evidence that land claimed from the Kopaic marshes was dedicated to agriculture in the Mycenaean Period, much as the land has been turned over to the cultivation of staple, fodder, and cash crops today. Firstly, the massive walls of Glas, constructed of roughly hewn limestone boulders, could hardly have been erected before the surrounding territory was free of floodwater. The fortress would thus have dominated an area of high agricultural potential. In addition, huge granaries have been discovered within Glas' walls, containing the charred remains of processed grain, and capable of storing several thousand metric tons of such cereals. This discovery may be understood in the context of records kept at the Mycenaean palace sites, such as those at Thebes, 15 kilometers south of Glas. These records, inscribed with characters of the Linear B syllabic script, indicate that the palace authorities were keenly interested in maintaining and expanding a certain economic regime of extensive agriculture, involving few crops, exploiting animal labor, and relying on technological investment. The drained Kopaic plain would have presented an ideal setting for such an agricultural strategy.

Documentary History

The Kopaïs during the mythic Heroic Age of Greece was thought to have contained dry ground cultivated by the Minyan inhabitants of Orkhomenos on its northwestern shore. Homer celebrated Orkhomenos for its wealth, and cultivation of the drained plain was the foundation of this wealth. The Greek geographer Strabo remarked in the first century BCE, "They say that the place now occupied by Lake Kopaïs was formerly dry ground, and that it was tilled in all kinds of ways when it was subject to the Orkhomenians" (Str. 9.2.40). The hero Herakles was said to have filled in the katavothres on the Basin's edge, causing the land to flood, in vengeance against the Orkhomenian king Erginos. Erginos had imposed blood-tribute on Herakles' native Thebes, the renowned city to the southeast. Herakles' revenge against Orkhomenos would have taken place a generation or two before the legendary Trojan War, that is in the final years of the 13th century BCE, according to Hellenistic chronologies (1194-1184 BCE per Eratosthenes, second century BCE).

Homer suggests that in his time (c. 8th century BCE) the Kopaïs contained the "Kephissian Lake" (Iliad 5.709), named after a major tributary river. From this time, if not earlier, until at least the last quarter of the fourth century BCE, the Basin appears to have remained a seasonally inundated wetland around a permanent lake no more than a few meters deep. Writing in the later fifth century, Aristophanes has a Theban merchant in his comedy Akharnians expressly mention delectable Kopaic eels and such native plants and animals associated with wetlands as pennyroyal (γλήχων), rushes, ducks, coots, grebes, and geese (Ach. 860 ff.). Theophrastos, Aristotle's famous student, writing in the middle of the fourth century, also describes the reeds and rushes of what he calls the "Orkhomenian Lake," and he explains how the lake expands due to rain in mid-winter and snow melting in spring, as well as describing the extraordinary floods occurring on average every nine years (C.P. 5.12.3; H.P. 4.11.2).

At some point between 335 and 332 BCE, Alexander the Great hired Krates of Khalkis in nearby Euboia to engineer means to mitigate flooding and claim land, presumably for agriculture, to benefit northern Boiotian cities. Krates' plan was twofold: to clear out the katavóthres and improve the cavern drainage with which they connected, and to dig a trench across the Kopaïs to draw floodwater into at least one of them. Strabo refers to a letter from Krates to Alexander that explained how he never completed the project because of political strife among the cities to be served, but that nevertheless some places had been drained, exposing ancient ruins especially in the southwest Kopaïs. Without maintenance, the improved sinkholes filled up with sediment and rockfall (Str. 9.2.18; see also St.Byz. Ἀθῆναι). Crop and soil marks (henceforth "field marks") indicate the presence of the "Krates Canal" emptying into the Vrystiká Katavóthra, to the south of Glas.

The Roman historian Livy, writing in the early first century BCE, describes how Boiotians waylaid Roman soldiers and murdered them "around the Kopaic swamps" (Livy 33.29.6). Pliny the Elder, another Latin author, writing in the first century CE in his Natural History about the reeds of the "Orkhomenian Lake" and the tributary Kephissos, alludes, as Theophrastos does, to unusually large inundations every nine or ten years (N.H. 16.66.169). Plutarch, a native of Khaironeia on the west side of the Kopaïs, writing a little later about the Roman Civil War between Sulla and Marius, two centuries before his time, describes the "marshes" below Orkhomenos, "in which the Melas loses itself" and eventually "unites with the Kephissos" in a place of "stagnant waters" (Sulla 20.2.4-5, Pelop. 26.3). He also alludes to the occasional "encroachment of the lake" on the city of Haliartos on the southern shore, further evidence of periodic large floods (de gen.Socr. 578).

Around 40 CE, according to a local inscription, a certain Epameinondas of Akraiphia donated 6,000 Roman denarii for the repair of an abandoned earthwork (χώρα χώματος), possibly of Mycenaean date, in the eastern end of the Bay, south of Glas, on the opposite side of Mt. Ptoion (IG 7.2712). An inscription of a few decades later indicates that Epameinondas lost his investment when the land reflooded (IG 7.2713). The next concerted effort to claim land from the Kopaïs came with the Roman Emperor Hadrian's investment of 65,000 denarii between about 125 and 135 CE, recorded in a series of monumental decrees at Koroneia on the western shore, for the construction of canals and aqueducts to serve several nearby cities (IG 7.2780, 2882; SEG 35.405). However successful these efforts may have been, the sponsored cities fell out among themselves, after Hadrian's death in 138, over appropriation of revenue, and the system was abandoned. An Imperial Period tomb at Ághios Dhimítrios in the western half of the Basin, just below modern estimates of the high-water mark (c. 95 m a.m.s.l.), may testify to the temporary success of this effort. Hadrian's sponsorship is the last known attempt to claim land from the Kopaic marshes in Classical Antiquity, and the Alexandrian and Roman projects appear to have had no direct impact on the northeast Kopaïs, wherein lies Glas.

No evidence is known of efforts toward general agricultural improvement of the Kopaic wetlands in the long period between the fall of the Western Roman Empire and the rise of the modern Greek nation-state. The 11th-12th-century cadastres of Byzantine Thebes provide no evidence of so much as irrigation works in the region. Ottoman records of the province of Eǧriboz (Classical Euripos), including the Kopaïs, indicate that rice was cultivated in the region from the 16th century with the help of irrigation works, particularly to the west. These may have been the restored Hadrianic works in part, as it was Ottoman imperial habit to refurbish ancient irrigation systems. Toward the end of this period, maize, which can tolerate exceptionally wet soils, was also grown on the borders of the Kopaic Lake. Records spanning the 16th to 18th century describe enormous wheat and barley harvests at Topólia, the community nearest to Glas. These crops grow well in the upland plains to the northwest of the town, and significantly, there are no records of rice in the same period.

Antiquarianism and Archaeology

Beginning in the late 17th century, Western European travelers with antiquarian interests passed through the region. Their main concern was to identify the sites of the events of Classical history and mythology. In 1676, the Swiss Jacob Spon and Englishman George Wheler visited the region together and noted the improved katavóthres and the remains of as many as five canals. Just before the Greek War of Independence against the Ottoman Empire, two Englishmen, George Dodwell and William Leake, made separate journeys through the Kopaïs. Dodwell observed the fortress of Glas and what he perceived to be a "summer road, or causeway" linking it to Mt. Ptoion, and he tentatively identified the site as Homer's Kopai. Leake, retracing the path of the Roman Period pilgrim and tourist Pausanias, was the first modern antiquarian to attribute the remains of drainage works to the Minyans of Orkhomenos. The German Heinrich Ulrichs visited in the 1830s. He expanded on Leake's attribution of the water management system to the ancient Minyans, arguing that they were responsible for the unfinished tunnel between the Bínia Katavóthra in the far northeast Kopaïs, and the sea at the Bay of Larymna. He also observed the tunnel from the eastern end of the Basin ("Bay of Akraiphia") and Lake Hylike (modern Likéri), as well as various improved sinkholes. Heinrich Schliemann, the last of the amateur German antiquarians and the "father of Mycenaean archaeology," excavated at Orkhomenos in 1880, including the Mycenaean tholos tomb traditionally called the "Treasury of King Minyas," and he provided rudimentary archaeological stratigraphy for part of the settlement. He adduced local epigraphy to identify the town of Topólia (modern Kástro), as opposed to Glas, with Homeric Kopai.

In the second half of the 19th century, a number of foreign companies, in cooperation with institutions of the Greek state, became interested in the agricultural potential of the drained Kopaïs. A French company undertook work to this end in 1882, though it soon stalled, and the British Lake Copais Limited Company took it over in 1887. When work was finally under way in earnest, it renewed interest among academic and amateur archaeologists in the drainage system of what was by this point understood to be the Greek Bronze Age. A series of relevant publications rapidly appeared. The engineer Michel Kambanis and the classicist Ernst Curtius virtually simultaneously concluded that the "Minyan" system of drainage consisted of improved katavóthres and several canals redirecting the major tributary rivers. Their conceptual reconstruction was an important advancement of knowledge, but it was incorrect in some details, since only the northernmost canal, channeling the Melas and Kephissos, is of Helladic date. Philippson, another German, included in the system the tunnel from the Bay of Akraiphia to Lake Hylike. He also shrewdly observed the need there would have been to divert water descending through canyons in the northeastern part of the Basin ("Bay of Topólia").

The year 1894 saw the publication of two studies of Glas: Ferdinand Noack's article "Arne" and Andre de Ridder's "Fouilles de Gha [sic]." Noack identified Glas with the Homeric city of Arne -- an identification that has persisted, despite repeated criticism by experts, including the eminent Boeotologist John Fossey. (Arne, if it existed, was surely on the west side of the Basin, perhaps near Classical Lebadeia.) Noack mapped several structures within both the inner and outer enceinte of Glas, the latter of which have lately been uncovered again, alongside further discoveries. He also discovered several contemporaneous fortified outposts or small settlements above Glas, including on Mt. Fteliá (eastern end of Ptoion) and at Aghía Marína Pýrghos, and he undertook careful study of the methods of construction of the fortifications and hydraulic works. De Ridder compared the cyclopean masonry of Glas directly with that of Tiryns in the core area of Mycenaean civilization, southern Greece, and he discovered within the inner walls a "fortified encampment" (later proved to be storehouses, not barracks), which cast doubt for the first time on whether Glas represented any city or town known to Homer.

After the British Lake Copais Company finished the modern drainage in 1931, investigators could make more precise analyses and careful interpretations. Before the Second World War, Ulrich Kahrstedt (German) and E.J.A. Kenny (English) criticized models of the ancient drainage works that would place everything in the same archaeological phase. Kenny determined in particular that the central drainage canal was that whose construction Krates of Khalkis had supervised, and he made the important discovery of a relatively small, localized rectilinear "dam" to the west and south of Tourloghiánnis -- another limestone "island," like Glas (about3 km distant) -- on the north shore of the Kopaic Basin. Perpetuating intensive German scholarship of the Kopaïs, especially its Mycenaean phase, Siegfried Lauffer took up Kenny's observations in the late 1930s and continued his studies after the War. His fieldwork for a settlement archaeology of the region made several further discoveries that have improved the understanding of the nature and chronology of the various phases of dike and canal engineering. He demonstrated stratigraphically that the beginning of one period of inundation of the Kopaïs corresponded to the end of the Helladic Period (i.e. c. 1200-1100 BCE) at sites on the west side of the Basin, and he observed an earlier phase of inundation that he placed at some point in the second millennium BCE. He recorded an eastern extension, possibly a later annex, to the Tourloghiánnis dike that Kenny had observed (thenceforth the "Kenny-Lauffer Dam"), concluding that it enclosed a polder -- that is, an area of land claimed from the marsh for human habitation -- and he likewise show that Glas was surrounded by dikes, "road-dams" (Staßendämme), and canals, constituting a polder.

Theodoros Spyropoulos' field studies strengthened and lent detail to Lauffer's observations. These included exploration of archaeological deposits in caves on the edge of the Kopaïs, identification of ruins in the Likéri and Paralímni lake beds to the east, and test excavations of dikes and fortifications. Discovery of Late Helladic IIIA pottery sherds in the latter led him to conclude that engineering began in the 14th century BCE. He also found evidence of use of the caves, perhaps for burials and rituals, dating from the Neolithic to the Middle Helladic Period, and he attributed the abandonment of these sites ot the first phase of Late Bronze Age drainage of the Kopaïs.

J. Knauss, B. Heinrich, and H. Kalcyk provided a masterful summary of the accumulated documentary, literary, and archaeological knowledge in their Die Wasserbauten der Minyer in der Kopais (1984). Jost Knauss has been especially concerned in this and subsequent works with writing a critical history of the investigations to date and with investigating the exact mechanisms of the ancient water regulation system. His field observations and precise reconstructions have supplied invaluable information on the complex system of dikes, canals, and polders in the northern Kopaïs and Bay of Topólia that encloses Tourloghiánnis, Topólia, and Glas. Furthermore, Knauss discovered aerial photographic evidence of human habitation of the polders, seen in crop and soil marks (field marks) to the west of Glas and south of Tourloghiánnis (which AROURA has enhanced through analysis of data from satellites). In addition, he found evidence of similar hydraulic engineering in southwest Boiotia near Thisbe and in Arkadia in the Peloponnese, especially around Orkhomenos-Kaphyai.

In the meantime, the Greek Archaeological Service was able to resume extensive excavation on the erstwhile island of Glas, after the Greek state appropriated in 1953 the farmland created by the Lake Copais Company. Ioannis Threspiadis, Superintendent of Antiquities in Boiotia at the time, carried these out between 1955 and his sudden death in 1961. Spyridon Iakovidis took over the task of publishing Threpsiadis' findings, which he followed with 10 years of further excavation. The efforts of both these eminent Greek archaeologists made it clearer and clearer that Glas was not a settlement, in the sense of an ancient town, but rather an enormous fortress comprising large storehouses and a relatively small, elite residential section. Iakovidis discovered remains of huge grain stores in Buildings H and K, representing at least 2,000 metric tons of cereals. He thereby made two powerful arguments in favor of the aims of AROURA: (1) that the massive fortification and its storehouses were built to purpose only after the drainage of the Basin; and (2) that the surrounding territory, including the polder, was most likely dedicated to agriculture. The former is confirmed by finds of pottery spanning the LH IIIB. Especially significant is that just one (einkorn, Triticum monococcum) or possibly two species (emmer, T. dicoccum too?) of wheat were represented, as opposed to four or more cereal species at contemporaneous, non-palatial sites elsewhere in Greece, and all the grain brought to Glas appears to have been threshed and cleaned elsewhere.

Prof. Christofilis Maggidis of Dickinson University, Pennsylvania, has recently resumed archaeological investigations at Glas, under the auspices of the Archaeological Society in Athens.


Overview of Methods and Techniques


A Topographical Model

The land holding and tribute texts of the Mycenaean Linear B archives at the palaces of Knossos, Pylos, Mycenae, Tiryns, and Thebes are consistent with an extensive agricultural strategy, implying inequality of means, especially in land and technology, and the aim of producing a surplus for a relatively large population. They consistently refer to a handful of crop types: two types of grain (perhaps one species of wheat and one of barley), figs, olives, and flax. Significantly, there is no record of pulses (legumes), staples in the Eastern Mediterranean since Neolithic times. This limited assortment of crops contrasts sharply with the wide range, including several species of legume and up to half of dozen varieties of grains, evident at smaller Late Bronze Age sites in Greece. Moreover, the Linear B texts record teams of plow oxen and men to drive them, especially on the da-mo (δᾶμος) land with which the scribes are particularly concerned.

The land holding archives provide measures of land in terms of seed corn (grain for sowing). The range of measurements recorded indicates low sowing density typical of broadcasting seed on open tracts of land tilled and manured by animals. Together with the records of crops types, large single-crop harvests, draft oxen, and calculation of tribute in kind from cultivable area, the land holding texts point emphatically to the Mycenaean palace scribes' concern with precisely administering a delimited system of discretely measured, extensively cultivated land plots. The polder created around the fortress of Glas in the Late Helladic III period would have been an ideal locale for practicing such agriculture, monitored and protected from the fortress. The storerooms therein have yielded remains of einkorn and emmer, as stated above, which may have been deliberately selected for the hydrological conditions in the polder.

Co-director Dr. Lane has devised a topographical model of palace-administered extensive agriculture that is applied in sampling and interpretation of results during AROURA. It is founded on the foregoing observations about the texts and archaeological data, and further inferences from historical, ethnographic, and agronomic sources about sowing density and plowing methods and rates. It assumes that land plots would have been laid out according to a regular pattern within a continuous expanse of arable land, as is typical of extensive agriculture, especially where such expanses are few and far between. The model also makes use of the asymmetrical Mycenaean system of dry measure fractions of seed corn to calculate not just the size of land plots but also their dimensions. Corroborating this schema is the late Emmett Bennett's masterly analysis of land holding texts from Pylos (AJA 1956), in which he showed, in topographic terms, that certain named o-na-te-re ("beneficiaries" of some sort) are clustered together in context with certain ko-to-no-o-ko ("land plot holders"). Hence the plots recorded either adjoined one another or they were, at least, close by. A regular pattern of land division would have facilitated the estimation of yield and assessment of taxes in agricultural products. This method of estimation is known from Bronze Age and Iron Age Mesopotamia and in Greece in later periods.

The field marks Knauss observed to the west of Glas in aerial photographs (see above), which are within and adjacent to the polder, bear a striking resemblance to Dr. Lane's hypothetical layout of a Mycenaean palace-sector field system. The smallest square formed by them is approximately 30 by 30 meters, or 0.09 hectares, nearly the area Lane has independently hypothesized Mycenaean area measure V 2 to be (0.091 ha). The next largest area outlined by field marks is approximately 30 by 90 meters, or 0.27 hectares, nearly the area he had independently hypothesized Mycenaean T 1 -- perhaps a day's plowing -- to be (0.273 ha).

Expected Finds and Appropriate Techniques

Hence AROURA has gone into the field with a clear set of expectations of what it should detect on or under the ground, as well as the scale of sampling necessary. These expectations include
* demarcated tracts of land tens and hundreds of meters in any dimension (corresponding to area fractions V and T, unit GRA, and multiples)
* rectilinear or near-rectilinear, built and excavated field partitions (e.g. trackways and ditches)
* built or excavated remains of outbuildings for crop processing, temporary shelter, or even defense
* pits for planting tree or vine crops, especially on peripheral foot-slopes, and
* plow scars in the subsoil from repeated plowing in one direction withing plots.

Appropriate techniques can therefore be applied. The principal technique employed on so expansive a sampling area -- some 1,000 hectares, with a goal of 6 percent sampled by 2012 -- is geophysical prospection, mainly magnetometry, because of its applicability anywhere contrast in magnetically susceptible iron oxides exists in soils. In particular, a dual fluxgate gradiometer is employed because it collects data rapidly in pedestrian traverse, and it can detect anomalies both near the surface and deeper than 1.5 meters. Critically, the magnetometric results are tested, or "ground-truthed," through cleaning and profiling modern irrigation ditch sections, and soil coring, the latter with a permit from the Hellenic Institute of Geology and Mineral Exploration. Samples of soil from the cores are floated and wet-sieved for recovery of macrobotanical, shell, and bone remains. Selected land tracts, especially at the site of Aghía Marína Pýrghos, are subject to collection of find from their surface, and multispectral satellite data are analyzed for ranges of values that correlate with geophysical anomalies. Finally, sediments and organic matter recovered from flotation are absolutely chronologically dated with accelerator mass spectrometry radiocarbon analysis and optically stimulated luminescence.


Research Questions

Major research questions at the outset were as follows.
1. What is the character (organization and orientation) of the land use, including evidence of agriculture, in the polder around Glas?
2. What is the specific nature, particularly geophysical and geomorphic, of the field marks observed in the polder surrounding Glas?
3. What is the relative or absolute temporal relationship between the fortress, major water-regulatory features (e.g. dikes and canals), and the field marks seen in the polder?
4. If direct evidence of agricultural practices or of sites of crop processing is discovered, what relationship can be established between it and that of food stores inside the fortress?
5. How precisely did the overall Mycenaean flood control system in the Bay of Topólia function, including the variable role of the katavothres, and how were the inflow and retention of desired water maintained?
6. When exactly did the local process of Late Helladic claiming of land begin, when did it eventually come to an end, and what is the exact sequence of construction inside the polder, including provisions for crop irrigation and potable water?

Specific sampling and exploratory objectives and quantitative goals are adaptive and change from year to year. They and the results of research may be found in AROURA annual reports.