5Katskhi Pillar Hermitage, Georgia
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For true isolation, it’s hard to beat the Katskhi Pillar in Georgia, a natural limestone monolith that rises 40 meters (130 feet) above the surrounding countryside. Atop this narrow pillar is a tiny church and a hermit’s house, where a solitary monk has lived for the past two decades. The hermitage is accessible only by a precarious metal ladder that ascends the sheer cliff face.