Lake Lagunitas sits within the Mount Tamalpais watershed in Greenbrae, and it’s one of those places where you can actually relax while your dog gets a decent workout. The main trail around the lake is a wide, well-maintained fire road with a flat grade—no scrambling, no steep climbs—which makes it genuinely easy for any dog, whether they’re young, old, or somewhere in between. The whole loop takes about an hour and covers roughly two miles, with plenty of shade from the surrounding trees so you’re not trudging around in full sun.

If an hour feels too short, you can extend things by heading over to nearby Bon Tempe Lake for an additional easy four-mile loop. Or if your dog has serious energy to burn, there are more challenging trails that branch off into the hills for exploring different parts of the Marin landscape. You’ll see other dogs here regularly, so most dogs get some natural socializing out of the experience.

Getting there from Highway 101, take the San Anselmo/Sir Francis Drake exit and head west on Drake toward Fairfax. After a couple of turns, watch for the wooden sign marking the entrance on Bolinas Road. Once you reach Sky Oaks Watershed Headquarters, you’re nearly there.

The important part: your dog needs to stay on a leash and stick to the designated trails. It’s not just a formality—it actually keeps everyone safer and protects the watershed. The trail gets decent foot traffic, which means good footing and clear paths, but also means you’ll want that leash secured. The area can get busy on weekends, particularly in good weather, so if you prefer a quieter experience, weekday mornings tend to be less crowded.