The State Park adjoins park lands of the East Bay Regional Park District, including Morgan Territory Regional Preserve, Brushy Peak Regional Preserve, Vasco Caves Regional Preserve, and Round Valley Regional Preserves. It also adjoins protected areas owned or controlled by local cities such as the Borges Ranch Historic Farm, the Concord Naval Weapons Station (now in the process of being converted to non military use), Indian Valley, Shell Ridge Open Space and Lime Ridge Open Spaces near city of Walnut Creek, and east to the Los Vaqueros Reservoir watershed, The new Marsh Creek State Park, and Black Diamond Mines Regional Preserve, are among the open spaces stretching back to the north. In this way the open spaces controlled by cities, the East Bay Regional Park District, Mount Diablo State Park, and various regional preserves now adjoin and protect much of the elevated regions of the mountain, with significant exceptions in Arroyo del cerro, Curry Canyon, the Marsh creek region and on the northern slopes of North Peak, and in a number of inholdings surrounded by preserve land.