Rockville Hills Regional Park
The park is 633 beautiful acres of grasslands and oak woodlands, with a dense mixed broadleaf forest. The rich, biological and diverse habitats provide shelter to a variety of wildlife that make the park their home. Rockville Hills in Fairfield is a popular mountain biking spot, but friendly for those on foot, as well. A number of trails should only be attempted by experienced riders while there are still plenty of beginner and intermediate level trails. Mountain bike rentals are available in the parking area. Entry fee is $3 a person and an extra $1 if you bring your dog(pricing subject to change).
Many of the trails feature fascinating rock formations, caves, and sweeping panoramic views of Fairfield and the Suisun marshes. Rockville Hills also features a lake and small pond, where fishing is permitted, as well as picnic areas.