Archaeologists reveal remains of the priory church of Groenendaal

Underneath the paths of the Sonian Forest are the remains of a large abbey: the priory of Groenendaal. The priory church was demolished in the 18th century, but this autumn, archaeologists revealed some of the walls, rooms and vaulted ceilings preserved underground.

© Stefaan Bockstal

A half-dilapidated shed on the edge of the Sonian Forest. Few hikers suspect that this is all that remains of an old abbey church. The old and dilapidated building is the lower part of the former church of the Au-gustinian priory of Groenendaal. The priory was founded in 1343 by mystic Jan van Ruusbroec. In 1783, the priory was dissolved and the church was partially demolished. In 1795, the Austrians delivered the finishing blow.




What did the church look like before? And which relics does the soil hide? Archaeologists investigated it last autumn. Archaeologist Jan Coenaerts of ABO Group: “We dug seven testing pits in and around the ruins of the church, of which only the nave is still standing today. We had expected to find graves, but this wasn’t the case. But we did dig up the former cloister, the walkway that runs around the square central section of the monastery. The choir of the church is also well-preserved. In addition, we found pits full of rubble. Those are the remains of the church that was demolished during the 18th century.”


© Marc Brion

The archaeological investigation is part of the plans to turn the site into a proper entrance gate to the Sonian Forest. The excavations are important to estimate whether restoring the priory church is possible and for which purpose the building might be used in the future. Jan Coenaerts: “We charted where and how far underground the remains are located. In our report, we indicate which valuable relics should be preserved. But also where the ground has already been disturbed and where construction works can take place in the future.”

Rare bats

Several parties cooperate closely as part of the research project: The Nature and Forest Agency, the Building Heritage Agency, the Vrije Universiteit Brussel, Tourism Flanders, the municipality of Hoeilaart, amateur archaeologists, nature guides, local historians and other volunteers. Not only is the site a treas-ury of historical patrimony, but the underground monastery rooms also house about ten different bat species, among which a few rare specimens.