This stone in Lake Geneva was once the reference point used to determine altitude in Switzerland.

The "geometrical" center of the country, as calculated in 1947.

This lesser-known geographic marker was the reference point for all surveys of the continent for 75 years.

This large copper bolt represents the benchmark for measuring sea levels in most of Europe.

This stone obelisk is a relic of the 17th-century Swedish mile markers.

The geographical center of Budapest is marked with a 10-foot-tall stylized zero.

An impressive century-old, to-scale topographical map of Guatemala.

Finding the exact middle of a giant land mass is hard to determine, but this spot managed to do the trick.