Topanga State Park () is a California state park located in the Santa Monica Mountains, within Los Angeles County, California. It is part of the Santa Monica Mountains National Recreation Area.

The park is located adjacent to the Topanga neighborhood of Los Angeles. Covering , with of trails and unimproved roads, the park's boundaries stretch from Topanga Canyon to Pacific Palisades and Mulholland Drive. There are more than 60 trail entrances. Topanga State Park is not only the largest park in the Santa Monica Mountains, but it is also considered the largest park located in the limits of a city. The Tongva and Chumash peoples inhabited the area for thousands of years. Residents and businesses were evicted and some buildings were demolished.

Businesses that remained included Cholada Thai, Malibu Feed Bin, Reel Inn, Topanga Ranch Motel, and Wylie’s Bait & Tackle Shop. On January 8, 2025, the Palisades Fire destroyed the structures housing these businesses. The fire also damaged a habitat site for monarch butterflies in Lower Topanga Canyon.

thumb|300px|Sunset on the trail to Trippet Ranch.

Natural history

Geologically, the park has many sedimentary sandstone rock formations, marine fossils, exposed faults, and volcanic intrusions.

Flora

The primary habitats in the park are of the Coastal sage scrub and montane chaparral and woodlands ecoregions. In Trippet Ranch there is a significant area of California oak woodland. The smaller habitats include bay laurel woodland (Umbellularia californica), walnut woodland (Juglans californica), and grassland savannah. The various types of plants and habitats are due to microclimate differences across the park.

Fauna

There are over eighty mammal species and more than sixty reptile and amphibian species. Snakes present include the Southern Pacific rattlesnake (Crotalus oreganus helleri). Topanga State Park is home to many species of migratory and resident bird species. Later, the $54 million figure was reported to be misrepresented, with the actual hidden surplus amounting to $20 million, still enough to cover the alleged shortfall that had prompted the plans to close as many as 70 California state parks. In February 2013 it was revealed that the approximately $20 million had been hidden for as long as 20 years by the California Department of Parks and Recreation.

Federal trail improvements

In August 2012, Congressman Brad Sherman announced that he secured federal funds to help improve parks and public areas. His first project was to help restore sections of the 65 mile Backbone Trail, one of the most popular trails in the park and the Santa Monica Mountains National Recreation Area. The Congressman said, "The Backbone Trail provides thousands of hikers, bicyclists and other outdoor enthusiasts with an unparalleled recreational experience through the heart of the Santa Monica Mountains. These improvements will enhance that experience and improve safety for everyone that uses this popular trail." The money is going to go to clearing back brush on the trails, fixing and preventing landslides along the trail, and repairing the Chicken Bridge in the park. Hikers have reported significant improvements to the trails, and the project was completed in 2013.

</references>

  • California State Parks: official Topanga State Park website
  • Topanga Canyon Docents — includes information about the park's nature center.
  • Image of young woman seated on a rock, Topanga Canyon in either the 1920s or 1930s. Los Angeles Times Photographic Archive (Collection 1429). UCLA Library Special Collections, Charles E. Young Research Library, University of California, Los Angeles.