Highly praised when it was installed, the polyptych was removed from the apse soon after 1555, dismantled, and its many panels dispersed.

WSJ: Separated at the Altar | Piero della Francesca in America | Frick Collection | By Karen Wilkin

This is a 12th-Century church, lined with a shimmering apse mosaic.

BBC: Going underground at the Colosseum