Los Peñasquitos Canyon Preserve is an urban park in San Diego, California. Stretching approximately 7 miles, the park encompasses some 4,000 acres of both Peñasquitos and Lopez canyons, and is one of the largest urban parks in the United States. The preserve is jointly owned and administered by the City of San Diego and the County of San Diego. Los Peñasquitos is also home to the historic Rancho Santa Maria de Los Peñasquitos, an adobe home built in the early 1820s.