South of Twin Peaks, Islais Creek runs through Glen Canyon, home to native wildflowers such as red columbine and silver lupine and beautiful rock outcrops of layered radiolarian chert. The canyon is an important spot for migratory songbirds seeking fresh water in the creek, one of just two in San Francisco that has not been completely culverted. Recently, volunteers and city workers have improved eroding trails, removed nonnative plants, and replanted native grasslands, coastal scrub, and riparian habitat. Among the park's remnant native species is the San Francisco forktail damselfly, reintroduced here in 1996.
The park also has a developed side, including a community center, sports fields, children's camp, and tennis courts. Behind the community center, a trail splits at the creek and extends along each side of the stream. The trail on the east side of the park is partially wheelchair accessible, but may be muddy in places. It leads to a dramatic rock outcrop, then proceeds steeply up to Diamond Heights Boulevard.
Getting there: From Glen Park BART, walk west on Bosworth Street; turn right on Elk. From I-280 north, take the San Jose Avenue exit, then turn right on Rousseau, and right on Bosworth. From I-280 south, exit at Monterey; after a sharp right at the end of the ramp, turn left on Diamond and left on Bosworth. Turn right on Elk. Dogs on leash only; no horses or bicycles.
Hike by Lou Sian, originally published in the April 2007 issue of Bay Nature magazine