One of the oldest and richest mines in Colorado, this jackpot still pays off today as tourists clamber aboard donkey-pulled ore carts for mine tours. The tunnel reaches the main Bobtail gold vein 1,100 feet into Bobtail Hill, a lode that produced some $5 million before owners switched to mining tourism in the 1950s. The town's distinctive dry-wall rock construction can be seen in the mine portal and foundation of the mine office.