Optymistychna Cave

Gypsum cave system in Korolivka, Ukraine

Optymistychna Cave (Ukrainian: Оптимістична, lit. 'optimistic') formerly known as Peshchera Optimistitscheskaya, is a gypsum cave located near the Ukrainian village of Korolivka, Chortkiv Raion, Ternopil Oblast. Approximately 264 km (164 mi) of passageways have been mapped within. As a result, it is the longest cave in Europe and the seventh-longest cave in the world.

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