Baljenac is a small island in the Adriatic Sea, located off the Dalmatian Coast of Croatia. Although it is only about 34 acres (14 hectares) in area, it contains a network of roughly 14 miles (23 km) of low stone walls — making it resemble a fingerprint from above. Baljenac is uninhabited; its walls were built by residents of the nearby island of Kaprije to separate crop fields and vineyards.
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43.703199°, 15.727591°
Source imagery: Maxar