Explore San Geronimo Ridge Road in Marin and you will find Kent Lake, a Caterpillar Trail, dense forest, and little to no people around! The 7-mile 1,700 ft elevation gain figure 8 hike follows Peter’s Dam to Grassy Knoll to San Geronimo Ridge Road to Boulder Springs trail to Caterpillar trail and back to San Geronimo Ridge Road is in the middle of the Marin Municipal Water District, Samuel P Taylor State Park and Gary Giacomini Open Space Preserve. Not many people hike out here on the open fire roads and rugged side trails so if you are looking for a nice hike with fewer people, this might just be your spot!
Marin Municipal Water District
Marin Municipal Water District is the main part of the land that we hiked on. The watershed provides water to Marin County as well as open space to hike and bike. Dual-purpose that works for everyone! Kent Lake is Marin’s largest reservoir and lowest in elevation in the chain of lakes that starts with Lake Lagunitas’ spillway pouring into Bon Tempe, which overflows into Alpine Lake and then drains down to Kent Lake.
There are several miles of hiking trails throughout the Marin Municipal Water District all the way up to Mount Tamalpais. The diversity of terrain, trees, and types of trails make this a hiker’s dream!
Peter’s Dam Fire Road
There are several ways to make your way to Kent Lake. One of the easiest is to park at the parking lot for Leo T. Cronin fish viewing area (for free) and walk across to Peter’s Dam Fire Road. Head in from here on a nice wide and well maintained fire road and up toward Peter’s Dam.
Peter’s Dam Fire Road is completely shaded until you start climbing up to the dam. From the top of the dam, you can see a portion of Kent Lake. If you turn around you can see above the tree canopy of the small canyon you just walked up from. The day we went there was still some fog hovering over the trees.
Enjoy your views of Kent Lake from here! Kent Lake was nice and calm in the morning with the sun’s reflection shimmering on top of the water. A wonderful start to the hike! Once you continue on Upper Peter’s Dam Fire Road you are once again in the shade of the trees and lose sight of the lake.
Grassy Knoll Road
After climbing up, you start to descend down on Grassy Knoll road with bay trees arching over the trail and fall colors popping from all the trees. Definitely worth the dip in the trail! We took the little spur that takes you down to Kent Lake. At the end of the spur, we found this perfectly secluded spot just right for a picnic with views of the lake! We paused here and enjoyed the complete quiet around us and serene views of small ripples making their way across Kent Lake.
There really isn’t a beach here, the edge sort of drops off and you can see some of the fallen trees in the lake. This creeps the bosslady out. Too many crime shows with weird things trapped underwater maybe. The views of Kent Lake were great though!
With break time over, we headed back up Grassy Knoll road. It’s a nice gentle ascent to reach San Geronimo Ridge Road. Hang a right!
San Geronimo Ridge Road
San Geronimo Ridge Road extends for a few miles along the ridge above San Geronimo Valley. At almost 1,000 feet up you can have some great views from parts of the ridge that open up. Most of it is tree-lined keeping you nice and partially shaded. It is more like a fire road giving us lots of room to hike side by side and keep up the conversations of our future dreams. This is our cherished quiet time together…which is why we also seek out less crowded trails.
Stay on San Geronimo Ridge Road for about .5 miles then head down Boulder Springs Trail. Boulder Springs trail is more narrow and the trees are much more dense. Stay on this for about .5 miles while you descend about 400 feet and enjoy the shade from the trees!
At Caterpillar Trail (cutest trail name!) hang a left and enjoy this lovely rugged trail for about 1 mile. Caterpillar trail is narrow and pretty level with a few ups and downs. This side is closest to the neighborhoods in San Geronimo Valley. Life is heard along this trail. Dogs barking at who knows what, cars cruising down Sir Francis Drake Blvd and this was the first spot we ran into mountain bikers. That has to be a tough ride up for them but the little ups and downs on the trail must be so fun to ride!
When the Caterpillar trail meets San Geronimo Ridge Road, hang a right. You have now completed one of the loops in this figure 8 hike! This part of San Geronimo Ridge Road was lined with orange leaves crunching underneath and yellow and orange leaves falling from above whenever a slight breeze came through. It was lovely to see this much fall color!
Stay on San Geronimo Ridge Road until you meet Peter’s Dam Fire Road again and retrace your steps back to Leo T Cronin fish viewing area.
Parking is free and there’s space for about 15 cars so get there early to find a spot. Portable potties at the Leo T Cronin fish viewing area. The figure 8 hike is 7 miles with 1,693 feet elevation gain/loss and is mostly shaded making it a great hike to do any time of year! Dogs on leash is ok. The nearest food would be determined on which way you came into this area. It is pretty remote with few options close by so bring a picnic!
Things We Love:
Hiking is way more enjoyable when you have the proper gear. It can get warm on the trails, even in November! The hubs wore Marmot’s Conveyor Tee on the hike. He often wears Marmot short sleeve shirts because they are soft, fit good, and have great color options! They also wick moisture and are UPF 30 sun protection. Perfect for hiking! Being comfortable as well as having the functionality makes for a better more relaxed hike. Leave a note below on what your favorite hiking gear is. We are always looking for suggestions!
Click the Amazon link below to check out the Marmot Conveyor tee and see if they have a color you like!