The Apostle Islands are an archipelago of 21 islands scattered across the southwestern corner of Lake Superior, off the northern tip of Wisconsin. The national lakeshore protects the islands plus 12 miles of mainland shoreline, and it is one of the quieter units in the National Park System.
The sea caves are the star attraction, carved by centuries of wave action into the red sandstone cliffs of the mainland and several islands. In winter they freeze into spectacular ice formations. Six historic lighthouses dot the islands, the largest concentration in any national park. The forests are old-growth in places, and bald eagles and black bears are resident.
Most visitors explore by kayak or tour boat from Bayfield, a small town on the mainland that serves as the gateway to the islands. The sailing season runs from roughly June through October.