Keystone Century Wall is a dry stacked yet mechanically connected retaining wall that evokes the old world charm of mason crafted structures. Random and rugged yet blended with color and character, these high strength concrete modules appear as natural stone, but have the latest built-in technology of the Keystone pin assured connection. Designed specifically for taller wall structures and heavy loading conditions, Keystone Century Wall blends the distinctive look and character of natural stone with structural integrity that lets you build with confidence.