- The area surrounding the base of the Mount Umunhum radar tower is CLOSED to public access at this time. Visitors can access the East Summit using a temporary covered walkway. More info.
- Additional closed areas within Sierra Azul Preserve are shown on the Preserve map.
Preserve Info
Hiking
Biking
Equestrian
Dogs on Leash
Wheelchair accessible
Restrooms
Overview
Just south of the Town of Los Gatos, on the east side of the Lexington Reservoir, sits Sierra Azul, the District's southernmost open space preserve. Translated Sierra Azul means "Blue Range." Encompassing more than 18,000 acres, this is the District's largest Preserve. Sierra Azul Preserve is a true wilderness area, yet surprisingly close to the urban areas of the South Bay, making it a popular destination.
Because of its size, Sierra Azul is divided into four areas: Kennedy Limekiln, Mount Umunhum, Cathedral Oaks, and Rancho do Guadalupe.
Dog, Bike and Equestrian Access Limited: Activities may not be designated on all trails within the Preserve-- always refer to the map and trail signage for where the activity is permitted.
Temporary Covid-19 Restrictions
- Face coverings are required when you can’t stay 6 feet away from persons you don’t live with. Many Midpen trails are narrow — wear a mask, bandanna or gaiter you can pull over your mouth and nose as needed.
- Paper maps are not available at preserves. Please download a map before leaving home or snap a photo of the signboard map before you hike.
Gallery
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Creek
© Midpen -
Trail and Mountains
© Midpen -
Grassy Hill and Clouds
© Midpen -
Woods Trail
Woods Trail © Dave Hood -
View from Trail
View from Bald Mountain Trail © Dave Hood
Features
- Mount Umunhum, one of the highest peaks in the Santa Cruz mountain range.
- Varied Environment. One can visit serpentine grasslands, hard, rocky, and steep chaparral, dense stands of bay trees, or quiet, shaded oak woodland forests. For the more hardy explorers, there are deep ravines and riparian corridors, some containing seasonal or year-round water flow.
- Abundant Wildlife. The entire Preserve is prime mountain lion habitat and also provides homes for deer, bobcats, coyotes, and many other species of animals.
- This Preserve has the beauty and ruggedness of an unspoiled wilderness and attracts visitors seeking a more vigorous hiking, biking, and equestrian experience.
How to Get Here
Kennedy-Limekiln Area
Parking is available at the Lexington Reservoir entrance to Sierra Azul, accessible from Highway 17.
- From southbound Highway 17, take the Bear Creek Road exit, cross over the highway, and go 0.4 miles north on Highway 17 to Alma Bridge Road.
- Proceed across the dam to the parking area (there is a parking fee) at Lexington Reservoir County Park.
- From the parking area, visitors can continue on Alma Bridge Road a short distance to the Limekiln Trail trailhead (gate #SA22), on the left side of the road. The Priest Rock Trail trailhead is a short distance further on the road (gate #SA21), also on the left side.
Get driving directions to Lexington Reservoir Parking Area
The trailhead for the Kennedy Trail is accessible from Kennedy Road in Los Gatos, approximately 1.5 miles west of its intersection with Shannon Road, at gate #SA01. There is very limited parking at this trailhead.
Get driving directions to Kennedy Road roadside parking
Mt. Umunhum Area
Mount Umunhum Summit Parking Area
- Located at the top of Mt. Umunhum road, approximately 5.3 miles past the intersection with Hicks Road.
- Exit Highway 85 at Camden Avenue. (From Southbound 85 turn left on Camden Avenue. From northbound 85 turn turn left on Branham Avenue, then left on Camden Avenue.)
- Travel on Camden Avenue. about 1.6 miles.
- Turn right on Hicks Road. Travel on Hicks Road about 6.3 miles.
- Turn right on Mt. Umunhum Road. Travel on Mt. Umunhum Road for 5.3 miles.
- The Preserve parking lot will be on the left and stairs will lead visitors to the Summit. 53 parking spaces are available, including 4 ADA spots. A limited number of accessible parking spaces are located 0.2 miles further up Mt. Umunhum Road within the passenger dropoff/turnaround area.
Bald Mountain Parking Area
- Located on Mt. Umunhum Road, approximately 1.7 miles past the intersection of Hicks Road.
- The Parking Area is on the left. 25 parking spaces available.
- Trailhead for Mt. Umunhum Trail and Bald Mountain Trail
Jacques Ridge Parking Lot
- Located near the intersection of Hicks Road and Mt. Umunhum Road.
- The Preserve parking lot is on the right.
- Trailhead for Woods Trail
Trails
Kennedy-Limekiln Area
The popular 2,920-acre Kennedy-Limekiln Area, is accessible from Kennedy Road in Los Gatos, and from Highway 17, adjacent to Lexington Reservoir County Park and St. Joseph's Hill Open Space Preserve.
- 15 miles of trails, providing hikers, bicyclists, and equestrians with some excellent, strenuous loop trails.
- Leashed dogs are allowed only on the trails in the Kennedy-Limekiln Area.
- Bicyclists: there is a 15 mph trail speed limit and helmets are required at all times.
The popular Kennedy Trail/Limekiln Trail loop covers over 14 miles, and includes nearly 2,000 feet in elevation gain.
Mount Umunhum Area
The Mount Umunhum Area features the 3,486-foot mountain named after the Ohlone word for "resting place of the hummingbird." This 11,646-acre area marks the southern end of the entire District, and includes the former Almaden Air Force Base, which was part of the early-warning radar network built during the Cold War.
Mt. Umunhum Trail – This new 3.7-mile trail extends from the Bald Mountain parking area to the Summit, crossing through the varied habitats of the mountain and offering incredible views of the valley below, the ridgelines above, and the other great peaks of the Bay Area. This multi-use trail offers moderate terrain for hikers, bicyclists, and horseback riders; and, at the summit, is the highest point on the Bay Area Ridge Trail. Trail usage from the Trailhead Shelter located 3.2 miles up the Mt. Umunhum Trail near the parking lot to the summit and all summit pathways is limited to hikers only.
At the top of Mount Umunhum, visitors can enjoy the 0.3-mile accessible pathway to the west summit that leads to the ceremonial circle, east summit view point, summit shelter, and interpretive displays.
Bald Mountain Trail – A 0.7 mile trail from the parking area to Bald Mountain, a grassy hillside offering expansive views of the Almaden Valley and the Mt. Hamilton range to the east.
Woods Trail – From the trailhead at the Jacques Ridge parking area, this trail winds around the north side of Mount Umunhum, climbing to near the summit of Mt. El Sombroso, before meeting the Kennedy and Limekiln Trails. To the east, this trail connects with the Wood Road Trail in Almaden Quicksilver County Park.
Barlow Road – This 1.8 mile trail winds up a steep hillside, connecting Woods Trail to the new Mt. Umunhum Trail.
Dogs are not allowed in the Mount Umunhum Area, including all parking lots and roads.
Cathedral Oaks and Rancho de Guadalupe Areas
There is no public access to these areas as the area is surrounded mostly by private property, making public access unavailable at this time.
Because of the limited access, there is no formal trail system. As the District continues to acquire property in this area, a trail system will be developed to accommodate safe, secure public use.
Trail Conditions
This information is updated as needed when trails are opened or closed, or when there is scheduled trail maintenance. Visit the full Trail Conditions page for more information.
History
In addition to its unique habitats and geological features, Mount Umunhum has an important role in the region’s local and cultural history. For millennia, Native Americans have celebrated their traditions and histories at Mount Umunhum. The word “Umunhum” means “resting place of the hummingbird”, and signifies the delivery of fire to the Amah Mutsun people.
From 1957 to 1980, the summit was the site of the former Almaden Air Force Station where it served as part of a network of radar stations. The square concrete structure at the top of Mount Umunhum was once the base for a large Cold War-era radar sail. The summit has been closed since 1980 when the base was decommissioned. The base was acquired by the District and added to the Sierra Azul Open Space Preserve in 1986. In 2009, Midpen received federal funding, which enabled Midpen to clean up the site. Over 3,000 cubic yards of hazardous materials, including lead paint, asbestos, fuel storage containers and PCB transformers were removed along with13,680 tons of concrete, asphalt, wood and other materials, 97% of which were recycled or reused.
Regulations
- Hours: Open half an hour before sunrise to half an hour after sunset.
- Dogs: Dogs are allowed only on designated trails in this Preserve. Must be controlled on a maximum 6-foot leash at all times. Dogs are allowed only in designated preserves or areas as posted. Dog walkers are required to bag and remove all dog waste from the Preserve by packing it out. Moving dog waste off trail is not permitted. In accordance with the Americans with Disabilities Act, Midpen accommodates service dogs in Preserves wherever we allow public access. For more information visit the Dog Access page.
- Bicycles: Are allowed on designated trails only (those shown on the map for bicycle use). Helmets are required. Observe the 15 mph trail speed limit (5 mph when passing). For more information visit the Bicycle Access page.
- Equestrians: Horses are allowed on designated trails in this Preserve. Helmets are recommended for all equestrians. For more information visit the Equestrian Access page.
- Groups: For safety reasons, permits are required for all groups of 20 or more people.
- Permits: A use permit is required for any activity or event which: may be attended by twenty (20) or more people; OR is advertised or noticed in any publication, poster, electronic posting or flyer; OR requests/requires a fee be paid for participation. Visit the Permit page for more information.
- Fires: Fires are prohibited in preserves.
- Smoking: Smoking is prohibited in preserves.
- Weapons: All weapons are prohibited in preserves.
- Plants & Wildlife: Please leave plants and animals undisturbed. If you encounter wildlife during a visit, do not approach, startle or feed it. Although wild animals are generally fearful of humans and will run away, some wildlife can be dangerous.
- Water Areas: Swimming, wading or engaging in any water-contact activity is prohibited.
Overview
Just south of the Town of Los Gatos, on the east side of the Lexington Reservoir, sits Sierra Azul, the District's southernmost open space preserve. Translated Sierra Azul means "Blue Range." Encompassing more than 18,000 acres, this is the District's largest Preserve. Sierra Azul Preserve is a true wilderness area, yet surprisingly close to the urban areas of the South Bay, making it a popular destination.
Because of its size, Sierra Azul is divided into four areas: Kennedy Limekiln, Mount Umunhum, Cathedral Oaks, and Rancho do Guadalupe.
Dog, Bike and Equestrian Access Limited: Activities may not be designated on all trails within the Preserve-- always refer to the map and trail signage for where the activity is permitted.
Temporary Covid-19 Restrictions
- Face coverings are required when you can’t stay 6 feet away from persons you don’t live with. Many Midpen trails are narrow — wear a mask, bandanna or gaiter you can pull over your mouth and nose as needed.
- Paper maps are not available at preserves. Please download a map before leaving home or snap a photo of the signboard map before you hike.
Features
- Mount Umunhum, one of the highest peaks in the Santa Cruz mountain range.
- Varied Environment. One can visit serpentine grasslands, hard, rocky, and steep chaparral, dense stands of bay trees, or quiet, shaded oak woodland forests. For the more hardy explorers, there are deep ravines and riparian corridors, some containing seasonal or year-round water flow.
- Abundant Wildlife. The entire Preserve is prime mountain lion habitat and also provides homes for deer, bobcats, coyotes, and many other species of animals.
- This Preserve has the beauty and ruggedness of an unspoiled wilderness and attracts visitors seeking a more vigorous hiking, biking, and equestrian experience.
-
© Midpen
-
© Midpen
-
© Midpen
-
Woods Trail © Dave Hood
-
View from Bald Mountain Trail © Dave Hood
Kennedy-Limekiln Area
Parking is available at the Lexington Reservoir entrance to Sierra Azul, accessible from Highway 17.
- From southbound Highway 17, take the Bear Creek Road exit, cross over the highway, and go 0.4 miles north on Highway 17 to Alma Bridge Road.
- Proceed across the dam to the parking area (there is a parking fee) at Lexington Reservoir County Park.
- From the parking area, visitors can continue on Alma Bridge Road a short distance to the Limekiln Trail trailhead (gate #SA22), on the left side of the road. The Priest Rock Trail trailhead is a short distance further on the road (gate #SA21), also on the left side.
Get driving directions to Lexington Reservoir Parking Area
The trailhead for the Kennedy Trail is accessible from Kennedy Road in Los Gatos, approximately 1.5 miles west of its intersection with Shannon Road, at gate #SA01. There is very limited parking at this trailhead.
Get driving directions to Kennedy Road roadside parking
Mt. Umunhum Area
Mount Umunhum Summit Parking Area
- Located at the top of Mt. Umunhum road, approximately 5.3 miles past the intersection with Hicks Road.
- Exit Highway 85 at Camden Avenue. (From Southbound 85 turn left on Camden Avenue. From northbound 85 turn turn left on Branham Avenue, then left on Camden Avenue.)
- Travel on Camden Avenue. about 1.6 miles.
- Turn right on Hicks Road. Travel on Hicks Road about 6.3 miles.
- Turn right on Mt. Umunhum Road. Travel on Mt. Umunhum Road for 5.3 miles.
- The Preserve parking lot will be on the left and stairs will lead visitors to the Summit. 53 parking spaces are available, including 4 ADA spots. A limited number of accessible parking spaces are located 0.2 miles further up Mt. Umunhum Road within the passenger dropoff/turnaround area.
Bald Mountain Parking Area
- Located on Mt. Umunhum Road, approximately 1.7 miles past the intersection of Hicks Road.
- The Parking Area is on the left. 25 parking spaces available.
- Trailhead for Mt. Umunhum Trail and Bald Mountain Trail
Jacques Ridge Parking Lot
- Located near the intersection of Hicks Road and Mt. Umunhum Road.
- The Preserve parking lot is on the right.
- Trailhead for Woods Trail
Trails
Kennedy-Limekiln Area
The popular 2,920-acre Kennedy-Limekiln Area, is accessible from Kennedy Road in Los Gatos, and from Highway 17, adjacent to Lexington Reservoir County Park and St. Joseph's Hill Open Space Preserve.
- 15 miles of trails, providing hikers, bicyclists, and equestrians with some excellent, strenuous loop trails.
- Leashed dogs are allowed only on the trails in the Kennedy-Limekiln Area.
- Bicyclists: there is a 15 mph trail speed limit and helmets are required at all times.
The popular Kennedy Trail/Limekiln Trail loop covers over 14 miles, and includes nearly 2,000 feet in elevation gain.
Mount Umunhum Area
The Mount Umunhum Area features the 3,486-foot mountain named after the Ohlone word for "resting place of the hummingbird." This 11,646-acre area marks the southern end of the entire District, and includes the former Almaden Air Force Base, which was part of the early-warning radar network built during the Cold War.
Mt. Umunhum Trail – This new 3.7-mile trail extends from the Bald Mountain parking area to the Summit, crossing through the varied habitats of the mountain and offering incredible views of the valley below, the ridgelines above, and the other great peaks of the Bay Area. This multi-use trail offers moderate terrain for hikers, bicyclists, and horseback riders; and, at the summit, is the highest point on the Bay Area Ridge Trail. Trail usage from the Trailhead Shelter located 3.2 miles up the Mt. Umunhum Trail near the parking lot to the summit and all summit pathways is limited to hikers only.
At the top of Mount Umunhum, visitors can enjoy the 0.3-mile accessible pathway to the west summit that leads to the ceremonial circle, east summit view point, summit shelter, and interpretive displays.
Bald Mountain Trail – A 0.7 mile trail from the parking area to Bald Mountain, a grassy hillside offering expansive views of the Almaden Valley and the Mt. Hamilton range to the east.
Woods Trail – From the trailhead at the Jacques Ridge parking area, this trail winds around the north side of Mount Umunhum, climbing to near the summit of Mt. El Sombroso, before meeting the Kennedy and Limekiln Trails. To the east, this trail connects with the Wood Road Trail in Almaden Quicksilver County Park.
Barlow Road – This 1.8 mile trail winds up a steep hillside, connecting Woods Trail to the new Mt. Umunhum Trail.
Dogs are not allowed in the Mount Umunhum Area, including all parking lots and roads.
Cathedral Oaks and Rancho de Guadalupe Areas
There is no public access to these areas as the area is surrounded mostly by private property, making public access unavailable at this time.
Because of the limited access, there is no formal trail system. As the District continues to acquire property in this area, a trail system will be developed to accommodate safe, secure public use.
Trail Conditions
This information is updated as needed when trails are opened or closed, or when there is scheduled trail maintenance. Visit the full Trail Conditions page for more information.
- The area surrounding the base of the Mount Umunhum radar tower is CLOSED to public access at this time. Visitors can access the East Summit using a temporary covered walkway. More info.
- Additional closed areas within Sierra Azul Preserve are shown on the Preserve map.
In addition to its unique habitats and geological features, Mount Umunhum has an important role in the region’s local and cultural history. For millennia, Native Americans have celebrated their traditions and histories at Mount Umunhum. The word “Umunhum” means “resting place of the hummingbird”, and signifies the delivery of fire to the Amah Mutsun people.
From 1957 to 1980, the summit was the site of the former Almaden Air Force Station where it served as part of a network of radar stations. The square concrete structure at the top of Mount Umunhum was once the base for a large Cold War-era radar sail. The summit has been closed since 1980 when the base was decommissioned. The base was acquired by the District and added to the Sierra Azul Open Space Preserve in 1986. In 2009, Midpen received federal funding, which enabled Midpen to clean up the site. Over 3,000 cubic yards of hazardous materials, including lead paint, asbestos, fuel storage containers and PCB transformers were removed along with13,680 tons of concrete, asphalt, wood and other materials, 97% of which were recycled or reused.
- Hours: Open half an hour before sunrise to half an hour after sunset.
- Dogs: Dogs are allowed only on designated trails in this Preserve. Must be controlled on a maximum 6-foot leash at all times. Dogs are allowed only in designated preserves or areas as posted. Dog walkers are required to bag and remove all dog waste from the Preserve by packing it out. Moving dog waste off trail is not permitted. In accordance with the Americans with Disabilities Act, Midpen accommodates service dogs in Preserves wherever we allow public access. For more information visit the Dog Access page.
- Bicycles: Are allowed on designated trails only (those shown on the map for bicycle use). Helmets are required. Observe the 15 mph trail speed limit (5 mph when passing). For more information visit the Bicycle Access page.
- Equestrians: Horses are allowed on designated trails in this Preserve. Helmets are recommended for all equestrians. For more information visit the Equestrian Access page.
- Groups: For safety reasons, permits are required for all groups of 20 or more people.
- Permits: A use permit is required for any activity or event which: may be attended by twenty (20) or more people; OR is advertised or noticed in any publication, poster, electronic posting or flyer; OR requests/requires a fee be paid for participation. Visit the Permit page for more information.
- Fires: Fires are prohibited in preserves.
- Smoking: Smoking is prohibited in preserves.
- Weapons: All weapons are prohibited in preserves.
- Plants & Wildlife: Please leave plants and animals undisturbed. If you encounter wildlife during a visit, do not approach, startle or feed it. Although wild animals are generally fearful of humans and will run away, some wildlife can be dangerous.
- Water Areas: Swimming, wading or engaging in any water-contact activity is prohibited.
Preserve Info
Hiking
Biking
Equestrian
Dogs on Leash
Wheelchair accessible
Restrooms
Hours
Preserves are open from one-half hour before official sunrise until one-half hour after official sunset.
Preserve Activities
There are no events scheduled at this preserve currently.