*The following is a guest post from my friend and old classmate, the lovely Emily Alpert!
Perched on the top of Mount Tamalpais, the Rock Spring Trail meanders through meadows, chaparral, and forests. The trailhead offers sweeping views of the white city of San Francisco and the Golden Gate Bridge. In the summer, Mount Tamalpais can be over 100 degrees above the fog line and 50 degrees below the fog line, but Rock Spring is a shady, but not too cool compromise.
The hike
After parking at Rock Spring Parking Lot off Pan Toll Road from Highway 1, take the meadow trail that is perpendicular to the parking lot and goes toward the forest.
At the first fork, take a right on the O’Brien Trail toward Barth’s Retreat and soon say farewell to the meadow. After a jaunt in the forest, you will start a steep incline through chaparral, a shrubby habitat unique to Mediterranean climates, and only found in California and Baja California in North America. My family calls this bowl the “Vale of the Bees” because you can frequently hear the hum of active pollinators.
The plateau at the top is a nice lunch spot, under pygmy cypress trees, with a view east toward rolling hills. These trees are stunted due to the serpentine rock they grow on.
Continue down the other side of the plateau until the fork. There is a pit toilet above the fork that can come in handy.
Take a left at the fork on the trail towards Lauren Dell. Just before Laurel Dell, take the left fork up Cataract Creek (Cataract Trail) towards the Rock Spring trailhead.
This section of the trail goes from forest to meadow to forest to meadow and back, following a lovely creek that sometimes has inviting pools in the late spring and early summer. The slight slope upwards will take you back to the parking lot.
Follow the trail along the edge of the initial meadow. This loop can also be done in reverse, or expanded to include a section across the road from the trailhead, on the other side of the mountain overlooking the Pacific Ocean. However, I do not recommend the spectacular ocean route on a hot summer day due to exposure.