The Pacific Ocean defines San Diego's western boundary, with the city of 1.4 million spreading across 372 square miles of coastal Southern California. Mediterranean climate creates near-perfect conditions year-round: winter temperatures average in the mid-60s, summers reach the mid-70s, and rainfall remains minimal. Topography varies dramatically from sea level beaches to peaks exceeding 1,500 feet in the inland areas. San Diego Bay creates a natural harbor that shaped the city's development, while multiple coastal mesas provide elevated building sites. The city extends from the Mexican border north to La Jolla, encompassing diverse terrain.