Published on 2026-08-04

A 45-meter high limestone arch on Mackinac Island

Arch Rock is a 45-meter high natural limestone arch visible on Mackinac Island. It bears witness to erosion phenomena linked to water level variations and glaciers formed 400 to 420 million years ago. This remarkable rock formation shares the island's geological features with the Devil's Kitchen and Skull Cave caves.
Île MackinacGéologie

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