For something often invisible and more or less arbitrary, geographic borders have an enormous impact. In the history of the global geopolitical land-grab, innumerable wars have sparked from bits of Earth that have been claimed by more than one—and sometimes several—different nations.

Other times, these territory disputes result from political, cartographic, or geographic anomalies, such as the tiny library that operates in two countries at once, the rare four-sided border at the summit of a mountain, and the jagged international boundary that splits a town like a wandering crack.

But sometimes these boundaries simply don’t get agreed upon. Today there more than 100 contested territories around the world, including a few particularly surprising cartographic feuds. Here are some of the most bizarre territorial face-offs in the world.