San Francisco's modern art museum has a respectable and worthwhile collection. All the big names are there, it's close to Union Square, and the building is remarkable.
It also has a very good cafe, specialising in Italian-inspired California cuisine. It's not a bad way to spend a few hours if you're tired of the hustle and bustle outside.
Alternatively, if you've just had enough of the art, it's a short walk to the Metreon, where you can blast your senses with IMAX movies to neutralize those Clyfford Stills.
151 Third Street (between Mission and Howard Streets), San Francisco, CA 94103; tel: (415) 357-4000, or www.sfmoma.org
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Handy tip: Thurs evenings are half price entrance fee & first Tues of every month is free.