Carson Falls, Marin County, California

Fun short winter hike especially after a good rainstorm, there are a lot of ways to get here, we took the "low route" through a ravine along a little brook before hiking over a hill and down again to the falls.  You can also park at the Azalea Hill Trailhead parking area (in fact driving past here is prohibited at times due to flooding and a gate will be closed across the road) and then go back across the street to take the "high route" along the top of a ridge - this way is the Pine Mountain Fire Road so easier to hike than the less traveled lower route through the ravine where the narrow trail is rough at times and has to cut across the brook a few times which could be a challenge after a rainstorm.

Battery Spencer & Kirby Cove, Marin Headlands, California

We love visiting the headlands in winter when there aren't many tourists, often empty early mornings in January, we made the mile trek down to the beach at Kirby Cove and didn't pass another soul had the beach to ourselves!

Sweeney Ridge, San Bruno/Pacifica, California

There are multiple ways to tackle Sweeney Ridge, we started from the popular Sneath Lane Trailhead in San Bruno but you can also approach from west in Pacifica.  There are some historical landmarks - the spot where the Spanish first discovered San Francisco Bay and an old Nike Missile Site.

Mendocino Headlands State Park, Mendocino, California

This is a fun but small coastal park to explore by the cozy seaside town of Mendocino.

Big River Beach, Mendocino, California

Big River Beach is a great place for the dog to play, but there's also an 8-mile trail (much of which is ADA accessible) along the river running inland.  Lots of wildlife to observe and fun to visit year round.

Rancho Corral de Tierra, Montara, California

The peninsula is generally not so dog-friendly but Rancho Corral de Tierra is federal land so dogs are allowed!  There are a ton of options for exploring this space, this is just one possibility with easy parking, but also has some strenuous climbs but we did it in the rain and still had fun!  This was Clipper Ridge to French Trail and back: https://www.nps.gov/goga/rcdt.htm