1991 Vallejo helicopter crash

Sonoma Creek is a 33.4-mile-long (53.8 km) stream in northern California. It is one of two principal drainages of southern Sonoma County, California, with headwaters rising in the rugged hills of Sugarloaf Ridge State Park and discharging to San Pablo Bay, the northern arm of San Francisco Bay. The watershed drained by Sonoma Creek is roughly equivalent to the wine region of Sonoma Valley, an area of about 170 square miles (440 km2). The State of California has designated the Sonoma Creek watershed as a “Critical Coastal Water Resource”. To the east of this generally rectangular watershed is the Napa River watershed, and to the west are the Petaluma River and Tolay Creek watersheds. This south flowing river drains the western slopes of the Mayacamas Range, the southern slopes of Annadel State Park and the eastern slopes of the Sonoma Mountains with intermittent winter flows in the higher tributary reaches. As the tributaries and headwaters reach the valley floor, a perennial stream cuts through scenic and valuable vineyards of Kenwood. Sonoma Creek veers west at Kenwood and cuts a gorge running parallel to Warm Springs Road, where it turns south to historic Glen Ellen, passing within one mile (1.6 kilometers) of Jack London State Historic Park and the Wolf House and thence southward paralleling Arnold Drive. In the city of Sonoma it is an urban creek which emerges into agricultural areas to the south. Finally, Sonoma Creek discharges to the vast Napa-Sonoma Marsh at the northern tip of San Pablo Bay. Principal tributaries to the creek include Yulupa Creek, Graham Creek, Calabazas Creek, Bear Creek, Schell Creek, and Fowler Creek.

Tubbs Island is an island in San Pablo Bay (an embayment of San Francisco Bay). It is in Sonoma County, California, and parts of it are managed as part of the Napa-Sonoma Marshes Wildlife Area. Its coordinates are 38°08′59″N 122°25′27″W, and the United States Geological Survey measured its elevation as 0 ft (0 m) in 1981. It, long with Island No. 1, Island No. 2 and Green Island, are labeled on a 1902 USGS map of the area.

San Pablo Bay National Wildlife Refuge is a 13,190-acre (53.4 km2) National Wildlife Refuge in California established in 1970. It extends along the northern shore of San Pablo Bay, from the mouth of the Petaluma River, to Tolay Creek, Sonoma Creek, and ending at Mare Island.

KDYA (1190 kHz), "Gospel 1190 The Light", is a commercial AM radio station owned by Salem Media Group and licensed to Vallejo, California, serving the San Francisco Bay Area. It broadcasts an urban gospel radio format, and is Northern California's only full-time urban gospel station reaching San Francisco, Sacramento, Santa Rosa and Stockton. The radio studios and offices are on Blume Drive in Richmond, California. KDYA is a daytimer, transmitting 3,000 watts, using a directional antenna. As 1190 AM is a clear channel frequency reserved for Class A KEX in Portland, Oregon, and XEWK-AM in Guadalajara, KDYA must sign off at sunset to avoid interference with these stations. The transmitter site is on Noble Road in Vallejo, on San Pablo Bay.

Sears Point is a prominent landform that juts into the San Pablo Bay in Sonoma County, California, United States. This hill is the southernmost peak of the Sonoma Mountains and forms the southwestern ridge above Tolay Lake. Starting with European settlement of this area in the mid-19th century considerable modification of the Napa Sonoma Marsh began to occur, such that in contemporary times, there is considerable upland between Sears Point and San Pablo Bay. Numerous local conservation organizations are presently working to restore hundreds of acres of these historic tidal wetlands as part of the Sears Point Wetlands and Watershed Restoration Project. The region can be accessed via State Route 37 or State Route 121. Sears Point was named after Franklin Sears, who settled on 600 acres (2.4 km2) south of Sonoma in 1851. Later, he partnered with his father-in-law to purchase some 15,000 acres (61 km2), part of which is the present day racetrack, Sonoma Raceway.

Skaggs Island Naval Communication Station is a former United States Navy installation located near California State Route 37 between Novato and Vallejo, California. It was a secretive, secure, and self-contained naval base, engaged in a number of communications and intelligence gathering functions for the Navy and other federal intelligence organizations. The 3,310-acre (13.4 km2) site was purchased by the Navy in 1941, and closed in 1993. The antennas continued to be used for some time after that, but by 2013 they were removed along with all of the remaining buildings.

Sonoma Raceway (originally known as Sears Point Raceway, Golden State International Raceway and Infineon Raceway) is a road course and dragstrip located at Sears Point in the southern Sonoma Mountains of Sonoma County, California. The road course features 12 turns on a hilly course with 160 ft (49 m) of total elevation change. It is host to one of the few NASCAR Cup Series races each year that are run on road courses. It has also played host to the IndyCar Series, the NHRA Camping World Drag Racing Series, and several other auto races and motorcycle races such as the American Federation of Motorcyclists series. Sonoma Raceway continues to host amateur, or club racing events with some open to the public. The largest such car club is the Sports Car Club of America. The track is 30 mi (48 km) north of San Francisco and Oakland. With the closure of Riverside International Raceway in Moreno Valley, California after the 1988 season, NASCAR wanted a West Coast road course event to replace it, and chose the Sears Point facility. Riverside Raceway was razed for the Moreno Valley Mall. In 2002, Sears Point Raceway was renamed after a corporate sponsor, Infineon Technologies. On March 7, 2012, it was announced that Infineon would not renew their contract for naming rights when the deal expired in May 2012.

The 1898 Mare Island earthquake occurred in Northern California on March 30 at 23:43 local time with a moment magnitude of 5.8–6.4 and a maximum Mercalli intensity of VIII–IX (Severe–Violent). Its area of perceptibility included much of northern and central California and western Nevada. Damage amounted to $350,000 (about $10,700,000 inflation adjusted to 2018) and was most pronounced on Mare Island, a peninsula in northern San Francisco Bay. While relatively strong effects there were attributed to vulnerable buildings, moderate effects elsewhere in the San Francisco Bay Area consisted of damaged or partially collapsed structures, and there were media reports of a small tsunami and mostly mild aftershocks that followed. The mechanism of the shock is unknown, but several independent investigations focused on different aspects to gain a better understanding of the intensity, magnitude, source fault, and epicenter of this pre-instrumental event. Most investigators placed it under or to the north of San Pablo Bay, though two earthquake catalogs gave specific coordinates that place it within the confines of the San Pablo Bay National Wildlife Refuge. One of the numerous strike-slip faults of the San Andreas Fault System in the North Bay are most often named as the source fault, but one seismologist's paper detailed how an unnamed dip-slip fault may have been responsible. Several more recent studies gave alternate perspectives that named specific faults as the origin.

Tolay Creek is a 12.5-mile-long (20.1 km) southward-flowing stream in southern Sonoma County, California, United States, which flows through Tolay Lake and ends in north San Pablo Bay.

Wingo is a ghost town located in Sonoma County, California in the United States. It can be found on older maps as a dot along the sloughs of Sonoma Creek, south of Sonoma and Schellville, and west of Buchli.

Little Island is a partially submerged marsh island in the Napa Slough, branching off from the Napa River upstream of San Pablo Bay (an embayment of San Francisco Bay). It is almost entirely in Napa County, California, although part of its southern tip is in Solano County; it is managed as part of the Napa-Sonoma Marshes Wildlife Area. Its coordinates are 38°10′48″N 122°21′05″W, and the United States Geological Survey measured its elevation as 3 ft (0.91 m) in 1981.

Island No. 1 (formerly called Cross Island) is a partially submerged island in the Napa River, upstream of San Pablo Bay (an embayment of San Francisco Bay). It is in Napa and Solano County, California, and parts of it are managed as part of the Napa-Sonoma Marshes Wildlife Area. Its coordinates are 38°08′35″N 122°20′40″W, and the United States Geological Survey measured its elevation as 3 ft (0.91 m) in 1981. It, along with Island No. 2, Green Island and Tubbs Island, are labeled on a 1902 USGS map of the area.