67N 33W - Survey Map of Islands, Houghton Township, Isle Royale County

A survey map of Island No. 12 of the Isle Royale Group near Houghton Township in Isle Royale County, Michigan, measured between 1847 and 1934.

A survey map of part of Houghton Township, including Blake's Point, and several surrounding islands in Isle Royale County, Michigan, measured in 1904.

A survey map of Cochran Island in the Isle Royale Group near Houghton Township in Isle Royale County, Michigan, measured in 1909.

A survey map of an island in Tobin's Harbor near Houghton Township in Isle Royale County, Michigan, measured in 1934.

A survey map of part of Houghton Township and several surrounding islands, including Dean Island and Green Isle, in Isle Royale County, Michigan, measured in 1917.

A survey map of Blake's Point and Scovelle Point in Houghton Township in Isle Royale County, Michigan, measured in 1913.

A survey map of part of Houghton Township, including Locke's Point, and several surrounding islands in Isle Royale County, Michigan, measured in 1904.