First ascent 1875 Easiest route Hiking | Topo map USGS Mount Wilson | |
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Elevation 5,963+ ft (1,818+ m) NAVD 88 Similar San Gabriel Peak, Mount Lowe, Strawberry Peak, Echo Mountain, Mount Lukens | ||
Mount Disappointment is a mountain in the San Gabriel Mountains in Los Angeles County, California with a summit elevation of 5,963+ feet (1,818+ m). It was named "Disappointment" in 1894 when USGS surveyors sighted it from the Santa Susana Mountains, believing it to be the highest point in the immediate area, decided to use it as their next triangulation point. When they reached the summit, however, they discovered that San Gabriel Peak half a mile (0.8 km) to the east was 167 feet (51 m) higher and so moved there instead.
Map of Mt Disappointment, California, USA
A Nike missile site was located there in 1955 and the summit was flattened to accommodate it. The missile site was abandoned in 1965. The mountain top is now an important telecommunications site for both commercial and government organizations.