Hillsborough is an incorporated town in San Mateo County, California, in the San Francisco Bay Area. Hillsborough is one of the wealthiest communities in America and has the highest income of places in the United States with populations of at least 10,000. It is located 17 miles (27 km) south of San Francisco on the San Francisco Peninsula, bordered by Burlingame to the north, San Mateo to the east, Highlands-Baywood Park to the south, and Interstate 280 to the west. The population was 11,273 as of 2013. The town is served by Hillsborough City School District.
Hillsborough’s landscape is dominated by large homes; the town zoning and subdivision ordinances require a 2,500-square-foot (230 m2) minimum house size and minimum lot size of 0.5 acres (2,000 m2). As a result, there are no apartments, condominiums or townhouses in the city limits; however, it is not unusual for the homes along the eastern edge of Hillsborough to face condominiums in neighboring Burlingame, sharing the ZIP code 94010.
The town has no commercial zoning and thus no businesses within the town limits; the only non-residential properties are the town’s four public and three private schools, town and county government facilities, a golf course, a country club, and a small park.
Hillsborough is located on the Rancho San Mateo Mexican land grant which was purchased by William Davis Merry Howard, son of a wealthy Hillsborough, New Hampshire, shipping magnate, in 1846. Howard settled his family in this area, which attracted wealthy San Franciscans. Hillsborough is near Burlingame. In 1910, Hillsborough residents voted to incorporate.
Geography and Environment
Hillsborough is located at 37°33′37″N 122°21′23″W.
According to the United States Census Bureau, the town has a total area of 6.2 square miles (16 km2), all of it land. The area’s considerably winding, hilly topography (unsurprising given the town’s name), and impossibility of a grid layout, make Hillsborough notoriously challenging to navigate. Many lots include fairly steep slopes, particularly the western side of the town, with the landscape generally flattening to the east as it descends from the 280 freeway to El Camino Real and the towns of Burlingame and San Mateo.
Two prominent streams drain the mostly wooded slopes of Hillsborough: San Mateo Creek and Cherry Creek. In both cases the upper watersheds are closed-canopy California oak woodlands, with dominant trees of Coast Live Oak, Pacific Madrone and California Bay.
The upper drainage area of San Mateo Creek in Hillsborough contains significant serpentinite outcrops, which are known habitats for several rare plant species including the San Mateo woolly sunflower. Other common plants include toyon, gooseberry, lupine, monkeyflower and coffeeberry. Commonly observed mammals include California mule deer, raccoons, opossum, coyotes, rabbits, squirrels, and skunks.
Hillsborough is bordered by Burlingame to the north, San Mateo to the east, Highlands-Baywood Park to the south, and Interstate 280 to the west.