History: Geology and Archaeology at the Plains of Waalsdorp
Geology and Archaeology at the Plains of Waalsdorp
TNO The Hague Waalsdorp is built on the plains known as the “Vlakte van Waalsdorp”. Based on the results of excavations and discoveries by both professional archaeologists, and by the activities and discoveries of amateur archaeologists (mostly employees of the earlier Physics Laboratory and the Measurement Building) insight has been gained into the history of the plain. The archaeological activities are recorded in reports and journal articles. The first director of the then “Measurement Building” Ir. JL van Soest, as an amateur, archaeologically mapped the plain before 1940 by noting the number of steps.
From these activities, insight has been gained that the plain underwent different phases over the centuries, both in the landscape as well as in its use. The area was about 1500 years before our era part of an expansive beach area on which dunes were formed in successive sand-drift periods. As a result, both the “old dunes” (before our era) and “young dunes” (in the Middle Ages) have been established. Dune valleys with peat growth arose between these dune rows, on which a forest developed later. Due to large-scale logging in the Middle Ages and by sand drifts, the rather bare Plain of Waalsdorp arose. The original (very old) layers came to the surface, a so-called ‘geological window’.
In the late Bronze Age (period -1100 to -700) and the late Iron Age (period -400 to 0), the valley was visited by groups of hunters who, on the northern edge, established (semi) permanent residences. In Roman times (-50 to 400) and later in the Middle Ages (1000 – 1500) attempts were made to establish more permanent residences on the plain and even to develop agricultural activities. This agricultural use was suddenly interrupted twice by rapid sand drifts with dune sand (beginning of the 13th and 14th/15th centuries). After this period, the existing dune landscape formed.
Utensils stemming from the period from the beginning of our era to the present, such as Roman mantle pins, buttons, coins, heads of tobacco pipes, and the like are currently present in the museum. From the second half of the 18th century (and possibly even earlier) the Plain of Waalsdorp served as a military training ground. Military history can be recognised from the many discoveries of ammunition rests, parts of weapons and equipment. Most of the settlement activities are found in pot shards. In addition, remains have been found of fireplaces of habitation or temporary stay and spit tracks of agricultural activity. The floor of the TNO location in The Hague Waalsdorp lies in the middle of medieval farmland.
- young dune
- natural soil on old dune
- medieval field layer
- humus layer with spit tracks
- peat
- old dune
Medieval ditches and fields found during the 1983 development
- Excavation pit (circumference)
- Identified ditch
- Reconstructed ditches
- Closed ditches
- Reconstructed closed ditches
Early military history at the Waalsdorper Plain: the ravelin
In the first water source bearing sand area in the dunes at the sea side of the Bourdon bell, a rake-shaped military construction was built between 1771 and 1778: a ravelin with an “entrance gate” in the middle (see figure below). After 1779, the ravelin was further expanded. This defence work was used to learn attacking and defending by artillery, engineers, pontoonniers, miners and sappers from the military schools in Delft, Honselaarsdijk and The Hague. Remains of military camps, such as fireplaces, have been uncovered. The ravelin was still drawn on an 1873 map; a drawing from 1934 shows only the text ‘ravelijn’ [2].