St. Andrew's Church, Biggleswade

This church contains some 13th and 14th century elements, but it has been remodeled and added to extensively over the centuries.

R.J. Withers designed the east-end stone reredos in 1877 and it was decorated with Venetian mosaics by Salviati in 1881.

Sources:
National Heritage
Rodney Burton on Wikimedia Commons
Derek Jones' flickr Photostream
Colin Hinson on Genuki