Baarle-Hertog is a divided town surrounded entirely by Dutch territory, parts of which are under Belgian sovereignty, other parts of which are Dutch and form the municipality of Baarle-Nassau. It can be very difficult to know what territories are what, so a system has been devised whereby next to the street number on every building is located a flag identifying the nationality of the property. The church with the onion dome is definitely Belgian. The Belgian population numbers approximately 2,000.