Satellite image of the Rhine-Meuse delta, showing the Brielse Meer (u)

The Brielse Meer or Lake Brielle is a long, narrow lake and former Dutch estuary islands of Voorne and Rozenburg, in the province of Zuid-Holland. It takes its name from Den Briel, a town on its shore. The Brielse Meer was made from two bits of cut-off river branch: the last bit of Nieuwe Maas river from the Botlek strait until the confluence with het Scheur, and the Brielse Maas estuary.

When the Brielse Maas silted up in the late nineteenth century, the Nieuwe Waterweg ship canal was constructed (1872) and het Scheur was separated from the Brielse Maas by a dam. As part of the Delta Works sea barrier constructions, the Brielse Maas was closed off at both ends, becoming the Brielse Meer.