Segmental retaining wall corner block and wall corner comprised of corner blocks

A corner block having spaced-apart front and rear sections interconnected by two laterally spaced-apart side sections that jointly define an internal cavity that extends completely through the block from a top face thereof to a bottom face thereof, an upper protrusion protruding upwardly from the top face of the rear section rearward of the cavity, and two inner protrusions protruding from a wall of the cavity into the cavity and being spaced apart at a bottom portion of the block to define a gap therebetween, the upper protrusion being located and dimensioned relative to the two inner protrusions so that two corner blocks that are mirror images of one another can be stacked one atop the other with the upper corner block rotated 90° relative to the lower corner block and the upper protrusion of the lower corner block fitted into the gap between the two inner protrusions of the upper corner block to interlock the upper and lower corner blocks.