Hillsborough is located a little south of San Francisco, close to Burlingame and San Mateo. With its proximity to Highway 280, it is a perfect place to live if you work in San Francisco. Hillsborough is one of the wealthiest cities in America and its exclusiveness is upheld by houses having to be a minimum of 2,500 sq.ft. on lots of at least a half-acre; this makes sure that housing is very expensive. Like Los Altos Hills and Atherton to the south, Hillsborough has no apartments, condos or townhomes within its city limits.