| Upper Las Virgenes Canyon Open Space Preserve | |
|---|---|
 Oak Tree at Upper Las Virgenes Canyon Preserve | |
   | |
| Coordinates | 34°11′03″N 118°42′06″W / 34.184187°N 118.701538°W |
| Area | 2,983 acres (12.07 km2) |
| Established | 2003 |
| Governing body | Santa Monica Mountains Conservancy |
The Upper Las Virgenes Canyon Open Space Preserve is a large open space nature preserve owned and operated by the Santa Monica Mountains Conservancy spanning nearly 3,000 acres (1,200 ha) in the Simi Hills of western Los Angeles County and eastern Ventura County.
Originally part of Ahmanson Ranch, this area was sold by Seattle-based Washington Mutual to the Santa Monica Mountains Conservancy in late 2003[1] after lengthy issues concerning development in the chaparral shrub forest and oak savanna understory and overstory Plant communities. It was previously called Ahmanson Ranch Park.