Rangers and the U.S. Coast Guard monitor marine channel 16. Licensed charter dive boat service is available in Bayfield. Lake charts and other publications, including The Unholy Apostles - Shipwreck Tales of the Apostle Islands , are available through mail order or at the headquarters visitor center in Bayfield. Learn more about boating in the Apostle Islands . Dive Site s Sea Caves and Cliffs Sandstone caves carved into shoreline cliffs by wave action.
Visibility varies due to erosion of clay soils into the lake.
Calm conditions necessary for access. Devils Island , north end. Stockton Island, southwest side. Historic Docks Submerged dock cribs near sandstone quarries active in 1890s. Basswood Island , southeast side.