The guided quarry tour takes you to an overlook of the Smith Quarry. At nearly 600 feet deep, it is the largest operating deep-hole, dimension granite quarry in the world. The tour is approximately 40 minutes in length and typically runs rain or shine. Our tours depart at 10:30, 11:30, 12:40, 1:40, and 2:40 . Tours are first come, first served.