These are also the typical rocks found in the many dry stream beds leading from the coves to the perennial streams. 41 toward Monteagle. Pea gravel is also frequently specified as the fill material for the sandboxes and playground areas of daycare centers and kindergartens. On occasion, sand is prepared by crushing the soft sandstone. The seam between the limestone layer below and the sandstone layer above is the zone of an interesting and significant geological interaction.
Water dripping through the sandstone begins to move laterally when it encounters the limestone.
Over time, the limestone is dissolved thus creating the familiar caves of the region. Ranging from small tubular openings in the limestone to huge underground caverns reaching for miles, the Cumberland Plateau area is home to some of the most interesting speological sites in North America. While nearby Russell Cave in Doran Cove is nationally famous for the antiquity of its Amerindian remains, many other caves in the region were also used by the Indians. A number of limestone quarries are located around the region, the largest seen on I-24 approaching Chattanooga from the west. Smaller quarries in Franklin County are located in Cowan, near Decherd on Rt.