[1] MLO is located approximately 75 kilometers (47 mi) east of downtown San Diego, California, on the eastern edge of Cleveland National Forest, in the Laguna Mountains on the SDSU Astronomy Campus near the hamlet of Mount Laguna.

MLO was dedicated on June 19, 1968, seven years after SDSU's Department of Astronomy[2] became an independent academic department of SDSU's College of Sciences.

The dedication took place during the 1968 summer meeting of the Astronomical Society of the Pacific.

[3] The telescope was operated in partnership with the University of Illinois at Urbana-Champaign (UIUC) until 2000.

Currently, SDSU is working with the University of Kansas (KU) and UNC Chapel Hill on various projects.