The Oklahoma City National Memorial was completed in 2001 to commemorate the 168 victims of the bombing of a Federal building in 1995.  It comprises 168 bronze and stone chairs with translucent glass bases that honour each victim individually.  It was designed by Hans and Torrey Butzer and Sven Berg.

The chairs are arranged in nine rows, representing the nine floors of the building that was attacked.  Each individual's chair is placed in the row the corresponds to the floor they worked on.

Photosensors are installed so that the chairs start to glow as darkness falls, turning them, in the words of the designers, into "168 beacons of hope".

Learn about this and other elements of the memorial site here.