The oldest and most productive quicksilver mine of the US is located here in New Almaden, Santa Clara County; though the entrances to the older mine stand closed today. But the mining area can be visited as a part of the Santa Clara County Almaden Quicksilver County Park. It is a national historical landmark now and close by stands a museum carrying the ruins of it s rich past. The Almaden quicksilver park which also includes the Almaden Reservoir is yet another great location of this city. Nearby, one can locate and visit the Casa Grande Almaden Quicksilver Mining Museum. With time, the mines grew into beautiful parks here and serve as great recreational facilities.