Napa: Lower Oat Hill Mine-Bald Hill-Holms Place Trail Hike

Thursday, December 1, 2016

View the entire Google Web Album

Today the 8.3-mile long Oat Hill Mine Trail follows the original route between Calistoga and the western end of Aetna Springs Road in Pope Valley. The old mercury mines are further to the north and are not open to the public. The trail provides a magnificent recreational experience for hikers, mountain bicyclists. and equestrians, although the trail is rough and rocky in many places, and can be quite challenging. Visitors enjoy sweeping views of Napa Valley along the lower Oat Hill Mine Trail, while the middle and upper sections of the trail cross striking volcanic formations. The trail passes through a diverse mixture of Oak, Douglas Fir, Gray Pine and Cypress forests, chaparral, and grasslands. Spring wildflowers are exceptional.*1

This segment of Oat Hill Rd was completed in the early 1890’s to service the freight wagon traffic from the Oat Hill and neighboring mercury mines. From its beginning, Oat Hill Rd was open to the public as a county road, and traffic was allowed to pass over without toll. For those traveling to and from Lake County, the completion of this road allowed them the option to taking the expensive Lawley Toll Rd over Mt St Helena.*3

This out & back hike travels 4.5+ beautiful miles on the Lower Oat Hill Mine Trail up to Bald Hill and to the intersection of Palisades Trail & the Upper Oat Hill Mine Trail at Holms Place. Begin this hike from the Calistoga Trailhead at the corner of Hwy 29 & Silverado Trail. The gradual upslope takes you along the east side of Hwy 29 with views of the vineyards and residential homes.

The trail winds around the woodland to a gorgeous vista overlooking the valley vineyards. This trail follows the original 1870s mercury mine road as it climbs through woodlands, chaparral, and grasslands, offering sweeping views of Napa Valley, Mt. St. Helena and the western Mayacamas ridgeline. The trail is rough and rocky in many places, and can be quite challenging with an elevation gain of ~2,000′.*2

Oat Hill Mine Trail continues through the woodlands on a gentle grade with an occasional glimpse of the valley to the 1 Mile trail post.

The trail travels beneath the beautiful canopy of trees across the ravines for another mile to the 2 Mile trail post.

Oat Hill Mine Trail cuts through the manzanitas and chaparral to the next trail post.

The trail emerges out of the heavily wooded hillside into open grassland with wonderful valley views!

Oat Hill Mine continues across the grassy slope with views of the rocky outcroppings.

The trail turns rough as it travels past the large rock wall and boulder sized rock formations to the 3 Mile trail post.

Enjoy the glorious Napa Valley views!

Oat Hill Mine Trail cuts back through the brush-covered hillside onto rocky terrain.

The trail leads out across the grassland to an open clearing with fabulous views of bald Hill, Mt St Helena and the Palisades!

Go left off the trail for the short climb up Bald Hill at 1360 feet. The hill is an exposed andesite intrusive typical in volcanic fields.*3 

Enjoy the magnificent valley views and surrounding mountain ranges!

Enjoy the large clusters of volcanic intrusives!

Continue on Oat Hill Mine Trail, it steadily winds uphill on rocky terrain.

The trail crosses through a multitude of fascinating volcanic formations!

Ruts carved by heavy wagons traversing the soft volcanic rock are still visible along parts of the middle and upper trail.*1

Oat Hill Mine continues through the dramatic volcanic features up to the saddle along the crest of the ridge to the 4 Mile trail post.

Enjoy the magnificent views!

The trail continues to the northeast on rocky terrain through volcanic rock formations for the next half mile. From this point on, we will be in volcanic mudflows, agglomerate and welded tuffs (ash deposits that accumulated in a semi-molten state).These rocks represent the most violent of the eruptions in the volcanic field.*3

Wagon wheels were capped with steel treads to protect the wooden rims from abrasion. The wheels of countless numbers of wagons that passed over this road gradually cut ruts into the rock. *3

This rough stretch of the trail offers an excellent view of the Palisades. They are made up of alternating layers of volcanic deposits, including mudflows, agglomerates and welded tuffs.*3

The trail skirts the south flank of the Palisades as it continues northeast into the woodland to the Palisades Trail junction.

Turn left onto Palisades Trail and follow it to the old mining camp at Holms Place. Midway along the trail is the homestead property of Karl Gustov Holm, who built a log cabin on his 160-acre homestead in 1893, and added a new house in 1896. Parts of stone wall for his barn and a few old fruit trees remain today.*1

At this point, you can go further NE for 3.7 miles along the Upper Oat Hill Mine Trail to Aetna Springs Trailhead or make this your turnaround point.

We’re saving the Upper Trail for a return hike to this area. Return along Oat Hill Mine Trail to the 4 Mile trail post.

Oat Hill Mine Trail from the 4 Mile trail post to the 3 Mile trail post.

Oat Hill Mine Trail from the 3 Mile trail post to the 2 Mile trail post.

Oat Hill Mine Trail from the 2 Mile trail post to the 1 Mile trail post.

Oat Hill Mine Trail from the 1 Mile trail post back to the Calistoga Trailhead.

Oat Hill Mine Trail offers dramatic views of the vineyards around Calistoga Valley, Mt St Helena, the rocky Palisades bluffs and the stunning volcanic formations! It’s a gorgeous scenic out & back hike with gentle grades and loads of geological features!


9.9 Miles with 1880′ of elevation gain
Max elevation: 2319′
Time: 5.5 hours with multiple stops
Hike: Easy-moderate
Parking: Calistoga Trailhead-Oat Hill Mine Trail at the corner of Hwy 29/Silverado Trail
Additional free parking on Lake St, be careful when crossing the highway
No facilities
Bring plenty of water-there is none along the trail
Weather: Sunny and cool with clear blue skies. Temps ranged from the low 40’s to the high 50’s with NE winds.

Oat Hill Mine Trail Stats:
Distance: 8.25 total length from Calistoga to Aetna Springs Rd
Elevation gain: 2000′
Tread width-typical: 8′ wide
Tread width-minimum: 15″ wide
Running slope-typical: 3-5%
Cross slope-typical: 1%
Slopes-maximum: vertical steps, rocks and gullies up to 1-foot height.
This trail does not comply with the standards of the American With Disabilities Act. *1

View the interactive RGPS route map & profile


Print Trail Map



Leave a Comment

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s