Muir Woods National Monument

It’s hard to tear your eyes away from the magnificent giant redwood trees in this forest, but if you can, you may glimpse a shy bobcat streaking across the path or a chipmunk foraging for nuts. Some of the trees at Muir Woods National Monument are more than a thousand years old, and as you hike the 6mi (10km) of trails, it’s easy to convince yourself you’re the only person around. It’s particularly atmospheric on gray days when rain pitter-patters on the canopy and the forest floor comes alive with a host of bizarre insects, including bright yellow banana slugs.