One of the old Spanish-style buildings encircling the square in Old Town San Diego. According to the site, the earliest evidence of human habitation in the area of San Diego dates to about 7,000 BC, which is quite extraordinary, considering that the first human settlers in the Americas arrived about 11,000 years ago or so. Contact occurred fairly early in this area of California, when Juan Rodriguez Cabrillo made some early explorations in the 1540s. The area which now comprises Old Town San Diego is sometimes referred to as the birthplace of California, as the site of the first permanent Spanish settlement. Junipero Serra also established the first of California's twenty one missions in the area. At the base of the large hill, a small community of adobe dwellings was established in the 1820s, and the village had been named El Pueblo de San Diego by 1835. The state Department of Parks and Recreation founded the Old Town State Historic Park to preserve the structures and character of the site, which includes the plaza, museums, and various other buildings.
See http://www.oldtownsandiegoguide.com/history.html for more info!