Reply The historical marker, which sits at the corner of McDonough Street and West Trinity Place across from the former DeKalb County courthouse, was unveiled this weekend and installed by the Georgia Historical Society. (Marcus K. Garner/Patch) (Marcus K. Garner/Patch) DECATUR, GA — A new historical marker is now standing in Decatur Square to commemorate Martin Luther King, Jr. and a chapter of his legacy many may not know happened. The marker, which sits at the corner of McDonough Street and West Trinity Place across from the former DeKalb County courthouse, was unveiled this weekend and installed by the Georgia Historical Society — just steps away from where the former 30-foot Confederate obelisk stood in the Square for more than 100 years.