Consisting of 22 small islands in Lake Superior, the Apostle Islands hold some of the most magnificent sea caves in the world, especially during the winter months when they become temples of ice.
Known as the most stunning sea caves across all of the Great Lakes, (called sea caves despite technically being Lake caves) the pitted expanses and eroded caverns beneath the Apostle Islands are one of America’s most stunning natural wonders. Dotting the stacked stone walls of the island’s sides, the sea caves are arrayed like a delicate stone honeycomb. During the warmer months, these caves and tunnels are only accessible by boat with many of them too dangerous to enter. In the winter months, however, the caves turn into a more accessible and even more wondrous display.
As Lake Superior freezes over in the winter months, the otherwise damp caves and waterfalls also harden, covering the walls and ceilings with delicate ice formations. Once the ice of the lake hardens sufficiently, visitors can make the two-mile trek from the beach to the newly formed ice temples and view the fleeting beauty of the frozen chambers.
Millions of icicles and hundreds of ice floes are created in the Apostle Island Sea Caves each winter but the lake only periodically freezes sufficiently to allow safe access to them. Keep an eye on the National Park Service to see whether the weather is cold enough.