Morgan Territory is a regional preserve in California established in the late 20th century on the east side of Mount Diablo in the San Francisco East Bay's Contra Costa County. The acquisition and expansion of this territory has preserved important habitat and watersheds in the area for the public. Now an estimated 5,000 acres (20 km²), its creation has been a collaboration by public and private parties. It has been connected to Mount Diablo State Park by acquisition and transfer of properties between them.