Coyote Hills Regional Park is located right on the San Francisco Bay, and many of the trails provide amazing views of the Bay! One of the best trails, the Bay View trail, is paved and is open to bikes. The Red Hill trail is a fire road open to bikes and goes straight up and straight down the hills, providing amazing views but requiring some hiking unless you really keep your speed up. There are a number of other doubletrack trails spread across the park, including some trails heading straight out into the bay on levees with water on both sides! Unfortunately, all of the singletrack trails here are off limits to bikes. It's a pretty complex network, so be sure to study the map at the trailhead well and to check the signs.
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