While there are interesting hikes throughout the Bay Area, I think the North Bay has, far and away, the best hikes, be it in terms of scenery, wilderness, isolation etc.
You can't beat Point Reyes
for sheer awesomeness, and the hike to one of California's only tidefalls
is one of the most scenic in the state.
Another great coastal hike is a bit to the north at Red Hill
The most rugged and wild terrain in the Bay Area is found at the Palisades
. There are some great trails
among the cliffs.
Nearly as rugged but not quite as extensive is Hood Mountain
, which is one of the finest peaks in the Bay Area.
For those who hunt waterfalls, the North Bay has some amazing hidden gems: