South San Francisco

Sister cities

• Lucca

History

Parts of what is now South San Francisco have been populated for more than 5,000 years. and Buckeye shell-mounds on San Bruno Mountain. Charcoal-sampling indicates these ancient sites were actively occupied into the Spanish colonial period (late 1700s). The delta of Colma Creek was formerly an important habitat for the waterfowl known to be hunted by the Ramaytush in historic times, and archaeologic sites have been recorded near the creek. In 1835, the area which is now South San Francisco was confirmed to be part of Rancho Buri Buri, a large Mexican land grant to the Sanchez family, which they had used for cattle-ranching (with an easement for southbound traffic) for nearly a decade. While the Treaty of Guadalupe Hidalgo guaranteed the grant, taxes and legal-fees encouraged family-members to sell parts of the grant. Around that same time, the 12-Mile House was built as a stop on the San Jose Stage road. In 1853 SF butcher Charles Lux and business partner Alfred Edmondson, purchased in Rancho Buri Buri. In 1855 Lux bought another of Buri Buri land and soon partnered with fellow San Francisco butcher and entrepreneur Henry Miller, forming the stockyards and beef-raising firm of Miller & Lux. Lux bought out Edmonson's interest in 1856 and founded the town of Baden (now a neighborhood of South San Francisco) near the 12-Mile House. In 1863, Baden became a station as the San Francisco and San Jose Railroad was built. The city of South San Francisco was conceived as an industrial suburb and was promoted by representatives of the Beef Trust, a group including some of the country's largest meat packing firms. A city plan was put forward in 1888 by Gustavus Franklin Swift, founder of the Swift & Company meat packing firm. The plan called for multiple individual…

Geography

According to the United States Census Bureau, the city has an area of , of which is land and (69.50%) is water. The city provides some services to these areas. The city is particularly noted for the South San Francisco hillside sign on Sign Hill, which rises to the north of the city, with large white letters that proclaim, "South San Francisco, The Industrial City". The sign, a tribute to the city's industrial past, is listed on the National Register of Historic Places. South San Francisco, along with most of the Bay Area, has a mild mediterranean climate (Köppen climate classification Csb), with warm, dry summers and cool, relatively wet winters. Much of the valley faces east toward San Francisco Bay, affording bay views from higher levels. South San Francisco has mild winters and dry cool summers. The hills to the west shield the eastern parts of the city from some of the fog that prevails in neighboring areas. The microclimate of South San Francisco is dominated by wind from the nearby Pacific Ocean, which typically keeps the daytime temperatures quite cool year round, even during the summer months. January is the coolest month with August being the warmest month. The record highest temperature of and was recorded on June 14, 1961. The record lowest temperature of was recorded on December 9, 1972. Normal annual precipitation is . }} South San Francisco is frequently windy. Summer is the windiest season, with winds averaging ; winter is the least windy season, with winds averaging . {| class="wikitable" |- ! Month !! Jan !! Feb !! Mar !! Apr !! May !! Jun !! Jul !! Aug !! Sept !! Oct !! Nov !! Dec !! Annual |- | Wind (mph) || 7.2 || 8.6 || 10.5 || 12.2 || 13.4 || 14.0 || 13.6 || 12.8 || 11.1 || 9.4 || 7.5 || 7.1 || 10.6 |}

Race & ethnicity

Most-observed species

• Anna's Hummingbird

  Calypte anna (R.Lesson, 1829) · Aves
  91,944
• American Crow

  Corvus brachyrhynchos C.L.Brehm, 1822 · Aves
  81,539
• House Finch

  Haemorhous mexicanus (P.L.Statius Müller, 1776) · Aves
  77,122
• White-crowned Sparrow

  Zonotrichia leucophrys (J.R.Forster, 1772) · Aves
  72,348
• Black Phoebe

  Sayornis nigricans (Swainson, 1827) · Aves
  68,501
• Song Sparrow

  Melospiza melodia (A.Wilson, 1810) · Aves
  62,949
• Common Raven

  Corvus corax Linnaeus, 1758 · Aves
  60,848
• California Towhee

  Melozone crissalis (Vigors, 1839) · Aves
  60,768

Most recent

• M 2.58 — 2026-09-29
  6 km W of Yountville, CA
• M 2.63 — 2026-09-27
  26 km WSW of Westley, CA
• M 3.32 — 2026-09-27
  27 km WSW of Westley, CA
• M 2.51 — 2026-09-19
  10 km ENE of Milpitas, CA
• M 2.56 — 2026-09-17
  21 km E of Alum Rock, CA
• M 2.6 — 2026-09-16
  3 km ESE of Santa Rosa, CA