The city of Blokzijl at the former Zuiderzee was an enclave in Spanish grounds during the eighty years war with Spain and knew its greatest wealth during that period.
In the town otself is an old sea lock, which formed the mouth of the Steenwijker Aa from the 16th century onwards. Especially the peat, which was won in the back country, was a source of a lot of activity. The Dutch Reformed Church, the monumental buildings and the name of Blokzijl (which means fortified lock) date from this golden era. In museum ‘Het Gildenhuis’ (open afternoons only from 1.30 PM to 4.30 PM) the history of Blokzijl and its relationship with water is being depicted.