Poverty Ridge

The 2007 Alum Rock earthquake occurred on October 30 at 8:04 p.m. Pacific Daylight Time in Alum Rock Park in San Jose, in the U.S. state of California. It measured 5.6 on the moment magnitude scale and had a maximum Mercalli intensity of VI (Strong). The event was then the largest in the San Francisco Bay Area since the 1989 Loma Prieta earthquake, which measured 6.9 on the moment magnitude scale, but was later surpassed by the 2014 South Napa earthquake. Ground shaking from the Alum Rock quake reached San Francisco and Oakland and other points further north. Sixty thousand felt reports existed far beyond Santa Rosa, as far north as Eugene, Oregon.

Oak Ridge in Santa Clara County, California, is a ridge forming the east canyon wall of Arroyo Hondo, which drains into Calaveras Reservoir. Black Mountain is its highest point. The first known white settlers on Oak Ridge were the Parks family, who ran cattle on the ridge. Now owned by the San Francisco Water Department, the ridge is private property and is off-limits to most people.

Arroyo Hondo is a northwestward-flowing 13.0-mile-long (20.9 km) river in Santa Clara County, California, United States, that lies east of Milpitas. The area is privately owned by the San Francisco Water Department and is closed to public access because of its usage as drinking water. Bounded to the east by Oak Ridge and to the west by Poverty Ridge, Arroyo Hondo empties into the Calaveras Reservoir where it joins Calaveras Creek. It is formed by the confluence of Smith Creek and Isabel Creek which drain the west and east slopes of Mount Hamilton, respectively.

Black Mountain, also known as Mount Day, is a mountain in the Diablo Range of eastern Santa Clara County, California, east of Poverty Ridge and Arroyo Hondo, and about 10 miles (16 km) from Milpitas. The peak is one of the highest in area. The northern half of Black Mountain is an oak woodlands while the southern half is barren. Black Mountain can be clearly seen from most parts of the Santa Clara Valley including Sunnyvale, Cupertino, Mountain View and San Jose. The peak is visible from the Mount Hamilton and Monument Peak.

Los Buellis Hills are a short sub−range of hills in the northwestern Diablo Range, in the South Bay region of the San Francisco Bay Area, within Santa Clara County, California.

The Blue Oak Ranch Reserve, a unit of the University of California Natural Reserve System, is an ecological reserve and biological field station in Santa Clara County, California. It is located on 3,260 acres (13.2 km2) in the Diablo Range, northwest of Mount Hamilton, at 1,500 ft (460 m) elevation. The land, part of the 19th century Mexican land grant of Rancho Cañada de Pala, was donated to the University of California on December 1, 2007 by the Blue Oak Ranch Trust, an anonymous benefactor. Overnight accommodations for academic researchers and educational groups may be made by permission only.

Sierra Vista Open Space Preserve is a 1,678-acre nature preserve in the eastern foothills of Santa Clara County, California. The preserve is managed by the Santa Clara Valley Open Space Authority and was opened to public in 2002. The only access to the preserve had been from Alum Rock Park until 2014, when a new parking lot and trailhead opened along Sierra Road.

Calaveras Valley is a valley east of Milpitas, California in the San Francisco Bay Area. It has formed primarily as a result of the actions of the Calaveras Fault. The southern end of the Calaveras Valley is a few miles south of Calaveras Reservoir, while the northern end is at Sunol. See Calaveras Reservoir for more information.

Isabel Creek is a 18-mile-long (29 km) perennial stream which flows northwesterly along the eastern then northern flank of Mount Hamilton in Santa Clara County. It joins Smith Creek to form Arroyo Hondo north of Mt. Hamilton and is part of the southernmost Alameda Creek watershed.

Smith Creek is a 14-mile-long (23 km) perennial stream which flows along the western flank of Mount Hamilton in Santa Clara County. The creek begins near Bollinger Ridge, about 7.7 km SxSW of Mount Hamilton.

Rose Peak is a peak in the Diablo Range of California and is the officially listed highest point in Alameda County, though other sources claim the high point is actually nearby Discovery Peak.

Calaveras Reservoir is located primarily in Santa Clara County, California, with a small portion and its dam in Alameda County, California. In Spanish, Calaveras means "skulls". The reservoir is fed mainly by Arroyo Hondo and Calaveras Creek. Lying in the Calaveras Valley, the region is geologically active with the Calaveras Fault parallel to and to the west of the dam site. The seismic hazard forced replacement of the original dam. The replacement dam began construction in 2011 and was completed in 2019. The Calaveras Valley has diverse wildlife including deer, coyotes, squirrels, turkey vultures, red-winged blackbirds, yellow-billed magpies, red-tailed hawks, brewer's blackbirds, purple martins, barn swallows, bullock's orioles, and warblers. Since at least 2008, a pair of bald eagles has nested regularly.