The island is connected to mainland Maine by a bridge. It is also connected to Chebeague Island by a 15-minute ferry ride on the Chebeague Transportation Company's ferry, the Islander. The island's southwestern peninsula is the site of the Wyman Energy Center, an oil-fired electric power plant capable of producing up to 823 megawatts of electricity. Wyman is a peaking power plant, which means it is only fired up to operate during times of high electricity demand in the region, such as hot summer days.
According to the United States Census Bureau, the CDP has a total area of 2.0 square miles (5.1 km2), of which 1.0 square mile (2.7 km2) is land and 0.93 square miles (2.4 km2), or 46.51%, is water.