It is located about 14 km south of the city of Rotterdam, next to Mijnsheerenland in the municipality of Hoeksche Waard.

[4] Westmaas developed after the Munnikenland was enclosed by a dike in 1439.

[6] Westmaas was a separate municipality between 1817 and 1984, when it became part of Binnenmaas.

[7] Since 1 January 2019, it is part of the new municipality Hoeksche Waard.

This South Holland location article is a stub.