Borders are strange and unique entities, mind-dependent but realised in mind-independent geography. It is this oddness that gives them their allure, drawing us to them. 

Hadrian’s Wall. The Berlin Wall. The Demilitarised Zone (DMZ) between South Korea and North Korea. The ‘Golden Triangle‘ between Thailand, Laos and Myanmar. The ‘Four Corners’ between Arizona, Colorado, New Mexico and Utah. All these borders are tourist attractions, drawing large numbers of visitors every year. Some of them, such as the Berlin Wall, are not even borders today - they mark historical borders. Why do tourists visit them? Why is ‘border tourism’ so popular? Part of the fascination we have for borders lies in what they are: peculiar, mind-dependent things.

Geographical borders exist, but not in an ordinary way. The OED defines such borders as a ‘boundary line which separates one country from another’ . Borders clearly exist: it is a geo-political fact that France borders Germany, that South Korea touches the North. Nations use borders to mark the limits of their sovereignty, to define territories, to monitor or control the flow of people and ideas.