Twin Peaks gets the tour buses. A short walk away, Tank Hill gets almost nobody. The Frisc puts the summit at 650 feet, at the eastern end of Clarendon Heights, and calls it often empty.
The view
People call it a bridge-to-bridge view, and The Frisc says that undersells it: a 227-degree sweep from the Pacific past the Outer Richmond to Bayview Hill. It takes in Point Reyes, the Marin Headlands, Mount Tamalpais, Angel Island, downtown and the East Bay hills. Right below the north edge is Cole Valley.
Why it's called Tank Hill
San Francisco Rec and Park says the 2.9-acre natural area is named for the Clarendon Heights water tank, built in the 1890s by the Spring Valley Water Company to store water pumped up from Laguna Honda. The Frisc adds that eucalyptus trees were planted after Pearl Harbor to camouflage the tank, and that the city removed the tank in 1957. Today only the circular concrete foundation remains.
The city owned the land from 1930, sold it as surplus in 1960 and, after neighbors pushed back against a plan for about 20 houses, bought it back in 1977 using Proposition J open-space money, according to The Frisc.
Nature
The Frisc says about 60 native plant and animal species live there. In spring and early summer look for wildflowers like checkerbloom, Douglas iris and California poppies, and kestrels and red-tailed hawks are often around. The hill's most striking feature is a jagged outcrop of Franciscan chert on its north edge.
How to get there
The Frisc describes two short, steep ways up: rustic wooden stairs on the south side just east of Twin Peaks Boulevard and Clarendon Avenue (almost across from Crown Terrace), and a trail from the east end of Belgrave Avenue. Rec and Park replaced the old Belgrave log stairs with Douglas fir box steps, which opened Sept. 15, 2016. Bring a layer; it's exposed and windy.
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