It is a large Victorian basilica-type red-brick building which is Grade II* listed.

The apse is decorated with 1,000 square feet (93 m2) of mosaics by Frank Brangwyn, which were completed in 1916.

They show scenes from St Aidan's life: feeding the poor, in Northumbria, preaching and the death of the saint.

They are said to be best viewed at noon on a sunny winter's day, when they are lit by the nave windows.

[1] The organ, dating from 1896, is by James Jepson Binns and is in unusual in being unmodified from its original condition.