San Diego is a city in southern California, across the border from Tijuana in Mexico. San Diego is noted for its large seaport and the San Diego Zoo, and is a popular tourist destination due to its Mediterranean climate. San Diego has a large military presence, including the U.S. Marine Corps' Camp Pendleton and Naval Base Coronado. San Diego was founded by the Spanish in the 17th century, and incorporated into the United States after the Mexican-American War. The San Diego metropolitan area, including the suburbs of Chula Vista, Imperial Beach, Coronado, and La Jolla, has a population of about 3 million people.