Phleger Estate is a gorgeous swath of second-growth redwoods in the Santa Cruz Mountains just west of Silicon Valley.
It's a remote section of Golden Gate National Recreation Area that gets few visitors, making it a prime getaway if you need a break from civilization.
This route starts on Skyline Boulevard, AKA Highway 35. Parking is free in a smattering of lots on the west side of Highway 35 on the fringe of Purisima Creek Redwoods Open Space Preserve.
Cross the roads and take these trails:
Skyline Trail > Lonely Trail > Raymundo Trail > Mount Redondo Trail > Lonely Trail > Skyline Trail.
Best time to go: this is all shaded so it's nice year-round. It will be fairly warm in the summer, but not nearly as hot as it can get in the valley.
This is all downhill at the start and all uphill on the way back; bring plenty of water and snacks to keep your energy up on the way back.
Be very careful crossing Highway 35; motorcycle riders in particular enjoy screaming down this section of highway.
If there's nowhere to park along Skyline Boulevard, you can enter via Huddart County Park via Kings Mountain Road (it's $5 to park). Take the Crystal Springs trail to Miramontes Trail to the Raymundo/Redondo loop. It's a 6.2-mile hike.
Driving directions: The parking area on Highway 35 is three-tenths of a mile north of Kings Mountain Road and 6.5 miles south of Highway 92, which you can take from either I-280 or U.S. 101 in San Mateo County.
If you're coming from San Jose and the South Bay, take Interstate 280 in San Mateo County to the Woodside Road exit (California Highway 84). Go west through town of Woodside for about 1.5 miles, then go right on Kings Mountain Road; stay on it till it reaches Highway 35, turn right and go 0.3 mile).