Portage Lake Observatory, operated by the University of Michigan near Dexter northwest of Ann Arbor, was built beginning in 1948 and functioned until 1975 as one of the university’s mid-20th-century observing sites. Its significance lay partly in the major instruments it housed and their later roles in American astronomy. The Heber Doust Curtis Telescope, a 0.92-meter Schmidt camera, began work there in 1950 before moving in 1967 to Cerro Tololo Inter-American Observatory in Chile as the Curtis Schmidt Telescope. A larger 1.32-meter reflecting telescope installed in 1969 was transferred after closure to Kitt Peak National Observatory, where it became the McGraw-Hill Telescope.