Trione-Annadel State Park

Trione-Annadel State Park is a large protected area in Sonoma County covering thousands of acres with diverse natural features. The landscape includes oak woodlands, volcanic rock formations, seasonal streams, meadows, redwood groves, grasslands, and a 26-acre lake that supports various plants and animals.

The park was established in 1971 to protect the natural landscape. The area beneath its current boundaries was once home to the Wymore Quarry, which extracted stone for San Francisco's streets and buildings from the late 1800s until the 1920s.

The park serves as a gathering place where locals come to hike, mountain bike, and ride horses along its many routes. These activities shape how people experience and connect with the natural landscape throughout the seasons.

The park provides roughly 40 kilometers of trails suitable for hiking, mountain biking, and horseback riding at various difficulty levels. Plan visits during cooler months since much of the terrain is exposed with limited shade from trees.

The park is home to rare California red-legged frogs found in Ledson Marsh, the same species mentioned in Mark Twain's famous tale about jumping frogs from Calaveras County. Spotting these frogs during a visit connects travelers to a story that inspired American literature.

Location: Sonoma County

Inception: 1971

Phone: +17075393911

Website: http://parks.ca.gov/?page_id=480

GPS coordinates: 38.42920,-122.62500

Latest update: December 9, 2025 18:49