Hallerbos

The Hallerbos sits atop the yellowish sand of the Brusselsian. This layer is up to 40m thick and does not occur in the Pajottenland. It is assumed to be a delta deposit from an earlier Maas delta. The sand here creates higher hilltops and steep, wooded slopes. The landscape of the Hallerbos is characterized by a fairly flat massif of about 120 m in height, and it is intersected from north to south by five small valleys, with bubbling springs in the valleys. The hilltops are covered with clay layers and the steep slopes with thick sand layers. Thanks to the forestation, there have been few changes in this varied relief since the last ice age. The oldest paths in the forest have developed in some places into deeply incised hollow roads.

Dromos