Mount Umunhum, the fourth highest peak in the Santa Cruz Mountains (elevation 3,486 ft), is situated in Santa Clara County, in the Sierra Azul Open Space Preserve. The name, Umunhum (pronounced "uhm-uhn-uhm"), is an Ohlone Native American word believed to mean "hummingbird" or "resting place of the hummingbird." This peak is easily recognizable from the San Francisco Bay Area because of a large radar tower situated on the summit, known locally as "the box" or "the cube." The summit is the site of the former Almaden Air Force Station, a general surveillance station that has been closed since 1980. Although it is situated in an open space preserve, the summit is currently off limits to the public due to hazardous materials (such as lead paint and asbestos), and unsafe, partially demolished structures. Plans are underway to restore the summit for public use, although it is estimated that this will not be completed until 2016 or later.