It is 17 km (11 mi) south of Dunkirk and also 20 km (12 mi) west of the Belgian border. The river Yser runs through Bollezeele.
Language
Bollezeele's local speech is traditionally a Flemish dialect, similar to that spoken on the other side of the border with Belgium; this led to the town's being included in the Atlas Linguarum Europae as one of the Germanic dialects in France (the others were all in either Alsace or Moselle).[4]