Sex and Drugs and Border Changes
Because of its political status, the uninhabited peninsula is off limits for Dutch police. And because of its geographic isolation, it is out of reach for their Belgian colleagues. These circumstances conspire to make the peninsula a sanctuary for unlicensed sunbathing, loud bacchanalia and unrestricted drug dealing. All of which might frighten the wild horses that are the only permanent residents of the wider area – officially a nature reserve, on both sides of the border.
http://bigthink.com/strange-maps/635-sex-and-drugs-and-border-changes