Priest's Grotto (also known as Ozerna Ukrainian: Озерна, meaning: "lake") is a cave in western Ukraine near the village of Strilkivtsi (Ukrainian: стрілківці), located within the Borshchiv Raion (District) of the Ternopil Oblast (Province). Priest's Grotto is part of the extensive gypsum giant cave system, and is one of the longest caves in the World with over 124 kilometres (77 mi) of explored passages. It is about 450 kilometers (280 mi) driving distance southwest of Kiev, and about 5.5 kilometers (3.4 mi) south of the district seat of Borshchiv.
Holocaust refuge :
In 1942–1944, during the Nazi occupation, several Jewish families lived in this and the nearby Verteba Cave (located 8 kilometers, or 5 miles, to the west in the town of Bilche Zolote). Some of these people never left the cave for 344 days, making this the longest recorded instance of uninterrupted cave habitation known. Although some of the Jews hiding in these caves were caught and exterminated by the Nazis, thirty-eight of them managed to survive the Holocaust of Ukrainian Jews until the area was liberated by the Red Army in April 1944.
These people would have almost certainly not survived, had they not sought shelter in these caves, since 95% of the Jews in Ukraine were exterminated. Moreover, this group included two families, which made their survival all the more remarkable, since only 1% of Ukrainian Jewish families survived the Holocaust intact. At first they hid in the Verteba Cave, however after the Germans discovered their presence there, they moved to the relatively unknown Priest's Grotto cave, where they managed to survive for the rest of the German occupation of the region. Some of the local Ukrainians helped the Jews by selling them food, but others came close to bringing down their destruction, at one point even attempting an armed assault against the Jewish men who were trying to haul sacks of grain into the entrance of the cave in the middle of the night.