Dillon Reservoir four ski-resorts. Arapahoe Basin is medium-sized resort that is approximately ten miles from the lake. Keystone Ski Resort is a large tourist destination that is located approximately five miles away. Breckenridge, which is one of the largest ski resorts in Colorado, is located approximately seven miles from Dillon Reservoir. Copper Mountain is located approximately eight miles from Dillon Reservoir. These resorts stay open all year round. The reservoir is also a center of attraction for the area. During the winter months, ice fishing and snowmobiling are common activities. For warmer months, the towns of Dillon and Frisco each have marinas
US 31–Island Lake Outlet Bridge part of the National Highway System. Island Lake Outlet, also known as the Pine River Channel, was dredged in 1870 to connect Lake Michigan to Lake Charlevoix through Round Lake. A total of five bridges have crossed the channel at this location; the first was a small footbridge built in 1869. The current bridge replaced a swing truss bridge built by the city of Charlevoix in 1901. The US 31–Island Lake Outlet Bridge was designed by the bridge division of the Michigan State Highway Department, led by George M. Foster, and by consulting engineers Haslett and Erdal. Plans were prepared