Trione-Annadel State Park is a state park in the U.S. state of California located near the northern end of Sonoma Valley, adjacent to Santa Rosa’s Spring Lake Regional Park. It offers numerous leisure opportunities on its 5,092-acre (2,040-hectare) grounds. The Trione-Annadel State Park, in the heart of Santa Rosa, is a popular destination for hikers and bikers, with miles of hiking, mountain biking, and trail riding routes.


Trione-Annadel State Park boasts an abundance of wildflowers from early spring through early summer, particularly on a hike around Lake Ilsanjo. April and May are the finest months to view the park’s wildflowers, but some plants bloom as early as January and as late as September.


  • No dogs are permitted on trails. Dogs are permitted only on Channel Drive (a paved road) within the park and are leashed, under your direction.
  • Bay Area District Order No. 660-16-036 prohibits the use of model aircraft (“drones”), unmanned aircraft systems (UAS), and gliders in the park.
  • E-bikes are considered motorized vehicles and are therefore prohibited in the park.


Lake Ilsanjo provides outstanding black bass and bluegill fishing. There are 15 hiking routes in the park. Canyon Path to Spring Creek Trail Loop is the best walking trail in Trione-Annadel State Park with an average hike duration of 2 hours and 44 minutes.

The park is only open for daytime use, from sunrise to sunset.


Other Park Regulations

  • No camping is permitted in the park. Fires, camp stoves, and grills are prohibited. Campsites are accessible at Spring Lake and at Sugarloaf Ridge State Park should you decide to camp.  
  • It is banned to collect or destroy anything in the park, even mushrooms. Observe that all vegetation and animals within the park are protected.
  • Off-trail riding is strictly forbidden. Bicycles and horses are allowed only on specific trails. 
  • Motorized vehicles are only permitted on the entrance road and in the parking lot.
  • Only Channel Drive and the parking lot accept canines. They must always be on a leash and are not permitted on the paths.
  • Lock your vehicle and remove all valuables. Do not litter! Bring your litter with you when you leave the park. 
  • Drinking water should be carried on the trails. Hunter Springs’ water is exclusive for horses.


Trione-Annadel State Park

6201 Channel Dr, Santa Rosa, CA 95409, United States
Phone: 707-539-3911
Head northeast toward Channel Dr
108 ft
Turn left onto Channel Dr
1.1 mi
Turn left onto Montgomery Dr
1.5 mi
Turn right onto Mission Blvd
0.2 mi
Turn right onto CA-12 E/State Hwy 12 E
0.4 mi
Turn left onto Acacia Ln then turn right
184 ft

Drive to your destination – Valley Dental Surgery & Implant Surgery 207 ft