Views from atop mountain peaks are awe inspiring. Hikes listed below are ordered from the most strenuous to the most easy. Some of the 'peaks' listed at the bottom are merely hills, not mountains.
Rose Peak in Ohlone Wilderness
Rose Peak is located right in the middle of the 20-mile Ohlone Wilderness Trail between Del Valle Regional Park in Livermore and Sunol Regional Wilderness in Sunol. So one may either hike from Del Valle, or from Sunol. Both hikes are 20 miles round trip. 360-degree views from Rose Peak are pretty awesome. Trails are rugged with some steep sections. The best season is spring when hills are lush green. The hike may also be done in early winters, before rains. Most of the route is in the open, so summer hikes become overly strenuous.
Some groups do an end to end hike as follows: they divide themselves into two sub-groups, start from both trailheads and meet at Rose Peak to swap their car keys.
The easier approach to Rose Peak is from Sunol. The elevation gain is a few hundred feet less.
Post Summit in Big Sur
Post Summit in Big Sur is along a lightly traversed trail along Cabezo Prieto Ridge. There are two approaches: from Andrew Molera State Park and from Pfeiffer Big Sur State Park.
One may do an end to end hike all along the Cabezo Prieto Ridge through Post Peak. For such an end-to-en hike, there is a challenge: the section between Post Peak and Mount Manuel was unmaintained in February 2012, going through thick brushes at some points. So either go with a group that knows the trail well, or be ready for some adventure.
An end to end hike from Andrew Molera to Pfeiffer Big Sur. Several steep sections. Unmaintained trail between Post Peak and Mount Manuel.
Manuel Peak in Big Sur
Mount Manuel in Big Sur is along a well maintained trail in Pfeiffer Big Sur Park. One may also approach Mount Manuel from Andrew Molera via the Cabezo Prieto Ridge Trail. Note that the section between Post Peak and Mount Manuel was unmaintained in February 2012, going through thick brushes at some points. So either go with a group that knows the trail well, or be ready for some adventure.
A strenuous hike from Andrew Molera to Pfeiffer Big Sur. Several steep sections. Awesome views from Post Peak. Many spots along the route for ocean views. Note that the section between Post Peak and Mount Manuel was unmaintained in February 2012.
High Peaks in Pinnacles
Pinnacles National Monument in Hollister has a section called High Peaks which offers majestic views of valleys below. Several different routes may be formed in Pinnacles that go through High Peaks.
Fantastic short hike going through Bear Gulch Cave and High Peaks which offer panoramic valley views of rock formations in Pinnacles. To enjoy walking through Bear Gulch Cave, make sure that it is open. Caves are closed to protect bats which occupy them for most of the year.
Great cardiovascular workout along this hike over green rolling hills and panoramic valley views.
Mission Peak in Fremont
Mission Peak is the most popular destination among fitness enthusiasts. The hike climbs 2100 ft in three miles. Views all along are pretty good. The hike is best done in spring when lush green grass carpets the valleys. In summers, many people start before dawn for awesome morning views of east bay as the sun rises in the east.
A night hike to Mission Peak offers fantastic views of city lights throughout the bay. Sometimes, mist engulfs the hills, making the hike mysterious.
Mount Burdell in Novato
Mount Burdell is in Novato. The popular route to the peak is from San Andreas Drive, with 1100 ft climb and 5.5 miles round trip. Some sections of the trail are steep. An alternative longer but gentler route is from Olompali State Historic Park.
A long but fantastic route through varied terrain covering all major trails in McNee Ranch and San Pedro Valley, including Montara Mountain.
Doud Peak in Big Sur
The hike to Doud Peak goes through a variety of different terrains: cool redwoods and open ridges. The hike is pretty strenuous. It is harder than Mission Peak (2100 ft, 6.0 miles). Even though the elevation gain and mileage is similar for the two hikes, Doud Peak is more challenging because elevation gain is not uniform — many sections are steeper.
Awesome hike through a redwood canyon, chaparral filled ridges and views of jagged Big Sur coastline. It is best to do the hike in the anti-clockwise direction for great ocean views when descending Rocky Ridge Trail.
East Peak in Mt Tamalpais
On a clear day, East Peak in Mt Tamalpais offers incredible views of San Pablo Bay and San Francisco Bay. Mt Tamalpais is criss-crossed by myriad trails, so there are multiple hikes to East Peak from different trailheads.
The shortest route to East Peak is from Fern Canyon Road, gaining 1600 ft in 2.5 miles. The views from Verna Dunshee Trail which goes around East Peak are pretty awesome. Parking is tight on Fern Canyon Road. Only three to four cars may be parked here.
A pleasant hike through a combination of forested and open trails, all the way to Black Mountain. Valley views from atop Black Mountain are pretty good.
Monument Peak in Milpitas
An awesome hike with great valley views in Ed Levin County Park. Slightly easier than the hike to Mission Peak. It is possible to form longer loops by going all the way to Mission Peak, which is connected by trails with Ed Levin County Park. Is is best to visit Monument Peak in spring when hills are lush green.
Great hike through green rolling hills with panoramic views of San Francisco Bay.
Mount St Helena in Napa Valley
Mt St Helena is the highest summit in Napa Valley. Great views of various towns occupying the land surrounding the peak. The initial section of the hike is through a forest. After a mile, the route is along a wide fire road that slowly makes its way to the top.
A gently graded hike to the highest summit in Napa Valley. Only the last few hundred feet of the route are steep.
Pine Mountain in Marin County
Pine Mountain in Mt Tamalpais Watershed area offers panoramic views of green valleys nearby and San Francisco Bay in the distance. The hike to Pine Mountain is along fire roads, in the open. A hike to Pine Mountain may be combined with hikes to nearby Carson Falls, a cascade of seasonal waterfalls with plenty of water after rains. For a longer trip, one may additionally visit Kent Lake. Pine Mountain may also be approached from the nearby Cascade Canyon Open Space Preserve via the unmarked but well maintained Happersberger Trail.
A route that explores all the trails in the western section of Cascade Canyon Open Space Preserve, all the way to Pine Mountain. The trails go through varied terrain like forests, creeks, waterfalls and ridges offering panoramic valley views.
Wildcat Peak in Oakland / Berkeley
Wildcat Peak in Tilden Regional Park is a popular destination for hikes starting from Tilden or the adjoining Wildcat Canyon Regional Park. A series of benches awaits you at Wildcat Peak.
A long hike through rolling hills with great views of Berkeley and San Franisco Bay. The last few miles are on a paved road.
Spikes Peak in Hollister
Spikes Peak in Pacheco goes over green rolling hills. The peak does not stand out prominently from its surroundings. Many different loops may be formed that go through Spikes Peak. The hike is best done in spring, after rains, for lush green hills and wildflowers.
A pleasant hike over green rolling hills. Plenty of wildflowers in spring. This route goes through three lakes: Diamond Lake, Bear Hide Lake and Dinosaur Lake. Along the eastern segments of the overall route, there are good views of San Luis Reservoir in the distance.
Fremont Older in Saratoga
Fremont Older in Saratoga has several hills that offer panoramic views: Hunter's Point, Maisie's Peak and Nob Hill.
Great hike through various vista points in Fremont Older.
Mummy Mountain in Gilroy
Mummy Mountain is a hill in Coyote Lake - Harvey Bear Ranch County Park in Gilroy. As of March 2011, it was not marked in the online trail map. However, it was shown in the park brochure with trail map that was available at the park entrance. The trail is parallel to Coyote Ridge Trail and Mendoza Trail, going through the point marked with a cross at elevation 1374'.
Great hike over green rolling hills with panoramic valley vies. Best visited in spring when hills are lush green.
Hiddenbrooke Summit in Vallejo
Hiddenbrooke Summit is reachable by a short hike from Bennington Drive through a combination of fire roads and single track trails. The views of Hiddenbrooke vally homes along the trail are pretty awesome.
Spectacular hike in Yosemite to awesome 360-degree views. Trails are gently graded but the total elevation gain is about 6000 ft, making it a long day hike. A significant portion of the route is common to the route for Half Dome.
A desert peak with outstanding views. One of the easier peaks listed by the Desert Peaks Section of Sierra Club, the route is a combination of cross country hiking and walking along a well maintained trail. If you enjoy desert peaks near Death Valley, check out DPS List of Peaks.