The archaeological evidence relating to Koudekerk is comparatively plentiful, mainly thanks to an excellent recent publication (Van Grinsven & Dijkstra 2006). Excavations in 1978-1979 covered an area of 1.7 hectares. The earliest habitation was found to date from around the beginning of the Christian era. This settlement is thought to have been abandoned as a result of the establishment of the Rhine limes. It lay on the opposite side of the river but probably still fell under the prata legionis, a fiscal zone where people might visit but not settle. On this basis, the chain of habitation and use may be extended into at least the third century and possibly the zone’s Roman imperial status cast an even longer shadow. The thread of continuous use, however, is a thin one, as the next Merovingian-Carolingian habitation phase is thought not to have started until around AD 500. Maybe this starting date, given the presence of some fifth-century brooches and mortar fragments, could be brought forward a little but it still leaves a gap of two centuries or more. Continuous occupation from Roman times onwards is ruled out, at any rate in the excavated area. Interestingly, the Early Medieval habitation occupied roughly the same site as that of the beginning of the first century AD.
The Early Medieval settlement lay midway between two former limes forts, 6 km upstream from Roomburg (fig. 11). Thus there was no direct link with a castellum site. Neither was it located on the bank of the Rhine, with which it had no navigable connection. An ancient crevasse gully connected to the Rhine bisected the habitation sit, but by Merovingian times most of it had already become filled with sediment and was merely used for drainage. The distance to the river was just a few hundred meters. This geography is reminiscent of De Geer and parallels are also found in the nature of the settlements. Merovingian-Carolingian Koudekerk was a complex of farms laid out on a rectangular grid system on either side of the rudimentary gully (fig. 10). The complex consisted of six farmsteads, each with a farmhouse, a well and the usual outhouses. There were six farms and maybe more since the excavation did not cover the entire settlement. No house plans were recorded but the evidence of their clearly recognizable sites indicates that they were rectangular longhouses measuring about 6 x 20 meters. All six or more are thought to have been occupied contemporaneously.
This evidence pertains to the Merovingian period. It is, however, doubtful that the excavations fully cover this period. No habitation traces of Carolingian times were found, though there were finds of the period. Could it be that the Carolingian settlement lay just outside the excavated area or were its traces obliterated by subsequent land use such as clay digging? Unfortunately, Koudekerk resembles De Geer even in the poor preservation of its archaeological features. Therefore we can only assume that the settlement pattern remained essentially unchanged. It is the finds which make it plausible that occupation at Koudekerk was continuous between AD 500 and 800/850.