It is a part of the municipality of De Bilt, and lies about 4 km north of Bilthoven.

A fen is a wetland characterized by sphagnum moss, peat and an alkaline or neutral pH.

Rendering this wetland into agricultural land was initiated by Bishop Godebald van Utrecht (1114–1127) when the Kromme Rijn ("Crooked Rhine") was dammed in 1122 at Wijk bij Duurstede.

The oldest settlement in the area is the village of Voordorp, which gradually became known as Blauwkapel because the chapel's interior was entirely blue.

Blauwkapel still exists and is part of the Waterline and Fort defense system established to protect the provinces of Holland from inland invaders by flooding the land strategically and building fortresses where flooding was not feasible.