Some US cities (LA is a prime example) take a lot of escaping from. Getting out of the urban tangle takes an hour or more. Not so San Francisco, and the San Francisco Bay Area in general. Not counting planned urban parks such as the magnificent Golden Gate Park, or beaches and marinas where the imprint of human activity is heavy, and of long duration, you can often appear to be so far from a city as to not be able to imagine one is nearby, and you can do this in less than half an hour.
Two great escapes from SF involve the wonderful California coast. It’s easy (by car) to head south from Pacifica on California Highway 1, and hop from beach park to scenic overlook as far south as San Diego. Or, even faster, one can go north across the Golden Gate Bridge (itself a major tourist destination), and reach the wild overlooks of the Marin Headlands in minutes. And, with a bit more investment of time (but still under 30 minutes), you can drive to the trailhead of the scenic and peaceful Tennessee Valley, and hike the easy trail that leads to a secluded beach.
This is a great way to get a feel for the coastal form of natural California, with rolling hills, gentle valleys with small streams and lagoons, and unexpected groves of trees. There is nothing spectacular here, as in Yosemite or Muir Woods – just peace, and slightly spicy-sweet aromas of plants, birdsong and the gentle sounds of the wind in the bushes and trees, and, growing in the distance, the sound of the surf. But most importantly, at least once in a while, no sirens, no traffic sounds, no rush of urban business and busy-ness. A chance to unwind. There are dozens of places like this within easy reach of San Francisco, but his one is amazingly simple to get to, and pays for the minor investment many times over.