This 108 acre preserve on the slopes above the town of Larkspur is composed of three separate pieces of land. The northernmost parcel (which is roughly bisected by the Citron Fire Road) is the scene of an ongoing battle between the dedicated volunteer corps known as the Green Gorillas, and a host of tenacious invasive, non-native plants. It is not uncommon to visit this area and find one or more of these hard-working folks sawing down an Acacia or Eucalyptus tree, or pulling broom plants.
This area was slated for development at one time, and in some places you can see the curbs and sidewalks that remain from this failed effort. The west end of Citron Fire Road leads to the King Mountain Loop Trail, a public trail easement that crosses through private property, circles the top of the mountain, and intersects the Contractors Trail leading to Larkspur Creek. These trails (although not actually on the preserve) are considered the heart of the King Mountain, as they wind through quiet forests relatively free of the non-native plants that cloak the lower slopes. The Contractors Trail re-enters MCOSD property just above the Dawn Falls Trail. Hiking south on this trail leads to the adjacent Blithedale Summit Preserve, the trail to the north leads up the canyon to the Baltimore Canyon Preserve.
From Hwy 101 in Larkspur, take exit 450B for Sir Francis Drake Blvd west 2.1 miles. Turn left onto College Ave, right onto Woodland Rd, left onto Evergreen Dr, second right to stay on Evergreen, left onto Ridgecrest Rd, and follow to end (dead end).
Visit walkbikemarin.org, transitandtrails.org, 511.org, or dial 511 to find out about alternative transportation and public transit options from your location.
With patience one could possibly see every species of woodpecker in Marin just by walking the loop trail. In the valley below look for amphibians like California Giant Salamanders and Ensatinas.