Maurice
Thorner Memorial Open Space Preserve,
Marin County Open Space Preserve,
Marin County
In brief:
1.9 mile out and back hike in a small preserve with grassland and rolling hills.
Getting there:
From US 101 in Marin County, exit San Anselmo/Sir Francis Drake. Drive about 11
miles west on Sir Francis Drake, and turn right onto Nicasio Valley Road. Drive
about 0.4 mile, then park on the side of the road near the open space gate.
Trailhead details:
No parking or entrance fees. Substantial roadside parking. No maps, drinking water,
or designated handicapped parking. Pit toilets inside Roy's Redwoods Preserve.
There is no direct public transportation to the preserve, but Golden Gate Transit
bus #23 services San Geronimo Valley Drive. From there you could walk about 0.5
mile to the trailhead
Gas, food, and lodging:
Gas, pay phone, stores and restaurants back east in Fairfax. For breakfast before,
or lunch after a hike, I recommend Two Bird Cafe on San Geronimo Valley Drive
in San Geronimo (visible from Sir Francis Drake). No camping.
Distance, category, and difficulty:
This 2 mile out and back hike is easy. The preserve's lowest elevation
is about 300 feet. Highest elevation is about 520 feet. Hiking is easy in this
small preserve.
Rules:
The preserve's single trail is closed to cyclists. Dogs are permitted.
The Official Story:
MCOSD's
Maurice Thorner page.
Marin County Department of Parks, Open Space, and Cultural Services: (415) 499-6387
Map Choices:
• Use AAA's San Francisco Bay Region map to get there
• Download the pdf
map from MCOSD
• Don and Kay Martin's Hiking Marin has a useful map of the preserve
and the surrounding area (order
this book from Amazon.com).
• Barry Spitz's Open Spaces (order
this book from Amazon.com)
Maurice
Thorner Open Space Preserve in a nutshell -- a printable, text-only
guide to the featured hike.
• View photos from this hike.
Maurice Thorner Memorial is a tiny 
and
little-known open space preserve near San Geronimo in Marin County. For years,
the only access was at the end of Lagunitas School Road, and the single trail
ended at a hilltop overlooking a golf course and Roy's Redwoods. In September
2000, MCOSD completed an extension connecting Maurice Thorner Memorial with Roy's
Redwoods (via the golf course bridge). This permits hikers to explore the two
small preserves in once visit.
Summer and autumn are best spent elsewhere. There
is little shade on the ridge, and Thorner Memorial lacks significant foliage trees.
The grassland retains some late spring wildflowers, and you might enjoy the preserve
in late winter, when the ridge is swathed in fresh green grass.
Although Thorner Memorial has its own trailhead
at the end of Lagunitas School Road, parking is limited there and restricted during
school hours. Roy's Redwoods Open Space Preserve provides easier access, and since
Thorner is small, you probably won't mind adding a little extra mileage to 
your
hike. Start at the open space gate on Nicasio Valley Road. Turn right (looks
like the path ends at the portable toilets, but it doesn't), and follow the
signposts for horse traffic. The narrow path, open to hikers and equestrians
only, goes right at the toilets, then becomes indistinct in a pretty redwood grove.
Stay to the right of the creekbed (although there's another trail on the other
side), and look for a path heading south out of the woods. Blackberry brambles
crowd the trail. The trail crosses a bridge; turn right on the far side.
Ascending easily, Loop Trail soon leaves the woods behind and enters grassland.
Nicasio Valley Road is visible as the trail parallels the road. After a few gentle
dips, the trail reaches an unsigned junction at 0.26 mile. Bear right and cross
the golf course bridge. At the end of the bridge, Thorner Ridge Trail begins
at an unsigned junction. Turn left.
Thorner Ridge Trail, 
open
to hikers and equestrians, ascends gently. Coyote brush is common, as are invasive
broom plants. You might see Ithuriel's spear, yellow mariposa lily, and clarkia
in late spring. Spiky teasel plants line the narrow path. There are nice views
past the golf course back to Roy's Redwoods. Thorner Ridge Trail crosses through
a patch of stunted blackberry and soon after reaches the ridge line, joining the
preserve's previously existing trail. Bear right.
Pure grassland is interrupted by occasional coyote
brush shrubs as the trail runs along the ridge at an easy grade. The lookout at
Samuel P. Taylor is visible to the west, as is the ridgeline in Giacomini Open
Space Preserve, to the south. A look back to the east reveals White's Hill and
Loma Alta. Thorner Ridge Trail approaches and then enters a compact forest of
madrone, coast live oak, big-leaf maple, California bay, nutmeg, and hazelnut.
Beware of poison oak. Switchbacks wind downhill, and as the trail reemerges into
grassland, the end of the preserve is in sight (you may want to turn around here).
The trail descends on broad switchbacks, and ends, at 0.97 mile, near a school.
Retrace your steps back to the trailhead.
Total distance: 1.94 miles
Last hiked: Wednesday, June 6, 2001
Go to Bay Area Hiker Home page
and
little-known open space preserve near San Geronimo in Marin County. For years,
the only access was at the end of Lagunitas School Road, and the single trail
ended at a hilltop overlooking a golf course and Roy's Redwoods. In September
2000, MCOSD completed an extension connecting Maurice Thorner Memorial with Roy's
Redwoods (via the golf course bridge). This permits hikers to explore the two
small preserves in once visit.
your
hike. Start at the open space gate on Nicasio Valley Road. Turn right (looks
like the path ends at the portable toilets, but it doesn't), and follow the
signposts for horse traffic. The narrow path, open to hikers and equestrians
only, goes right at the toilets, then becomes indistinct in a pretty redwood grove.
Stay to the right of the creekbed (although there's another trail on the other
side), and look for a path heading south out of the woods. Blackberry brambles
crowd the trail. The trail crosses a bridge; turn right on the far side.
Ascending easily, Loop Trail soon leaves the woods behind and enters grassland.
Nicasio Valley Road is visible as the trail parallels the road. After a few gentle
dips, the trail reaches an unsigned junction at 0.26 mile. Bear right and cross
the golf course bridge. At the end of the bridge, Thorner Ridge Trail begins
at an unsigned junction. Turn left.
open
to hikers and equestrians, ascends gently. Coyote brush is common, as are invasive
broom plants. You might see Ithuriel's spear, yellow mariposa lily, and clarkia
in late spring. Spiky teasel plants line the narrow path. There are nice views
past the golf course back to Roy's Redwoods. Thorner Ridge Trail crosses through
a patch of stunted blackberry and soon after reaches the ridge line, joining the
preserve's previously existing trail. Bear right.