The gate off of Burnett Avenue is currently closed to vehicles. Please use the gate off of Portola Drive to access the park by vehicle.
At 922 feet in elevation, Twin Peaks is second only to Mt. Davidson in height, offers spectacular views of the Bay Area, and is a world-famous tourist attraction. Originally called “Los Pechos de la Choca” (Breasts of the Maiden) by early Spanish settlers, these two adjacent peaks provide postcard views and a treasure trove of animal and plant diversity. Most visitors to Twin Peaks drive (or take a tourist bus), walk or bike to the north peak parking lot to enjoy 180-degree views of the Bay Area.
Many miss an opportunity to experience the coastal scrub and grassland communities of this 64-acre park. Similar to the Marin Headlands, Twin Peaks gives us an idea of how San Francisco’s hills and peaks looked before grazing and then development changed them forever. The vegetation is primarily a mix of grassland and coastal scrub. Expect strong winds as you hike among plants such as coyote brush, lizard tail, pearly everlasting and lupine. The endangered Mission Blue Butterfly has adapted to the strong winds and flies low to the ground from lupine to lupine. Native plants provide habitat for brush-nesting birds like the white-crowned sparrow and animals such as brush rabbits and coyotes.
The best way to see this landscape is to hike the 0.7 mile trail network that ascend the two peaks, where you will also find 360-degree views that surpass those at the north peak overlook. Additional trails follow the southern and eastern slopes of the park; be sure to stay on established trails to avoid poison oak and minimize erosion. To extend your hike, you can continue down Twin Peaks Blvd towards Portola Drive into Glen Canyon Park for a 1.2 mile Creek to Peaks Trail hike.
Mission Blue Butterfly
The mission blue butterfly is a federally listed endangered species that still survives in a few areas of San Francisco, Marin, and San Mateo counties. In 2009, 22 pregnant female mission blues were released on Twin Peaks, the only place this butterfly has survived within the city. Look for the light blue, quarter-sized butterfly in the park’s rocky grasslands, which contain the three species of lupine it uses for food and to lay its eggs. NAP has developed a recovery plan for the mission blue on Twin Peaks.
Silver lupine is one of the three native lupine species that provide habitat during different stages of this fascinating butterfly’s life. The female butterfly lays eggs on the lupine and feeds on its nectar. When the eggs hatch, the newly emerged caterpillar feeds on the inner parts of the lupine leaves. Once the caterpillar has obtained enough food energy for the winter, it crawls down to the base of the plant and goes dormant. The following spring the caterpillar will emerge to feed again and return to the ground to pupate, emerging from its cocoon as a butterfly. Like many butterfly species, mission blue’s larvae have a mutualistic relationship with ants. Caretaker ants stroke the larvae with their antennae, which causes them to secrete a sugary fluid, called honeydew, that the ants crave. In return, the ants protect the larvae from predators and parasites.
Street parking is widely available off of Crestline Drive and there is a small parking lot located near the Christmas Tree Viewing Area. Muni line 37 stops along Crestline Drive and Muni line 48 stops along Portola. Visitors should remain aware of their surroundings at all times. Do not leave valuable items unattended.