At the western side of the churchyard, Long Alley is the oldest almshouse, erected 1446, with the central porch added 1605 and lantern over the hall in 1707. The Master and Governors of Christ's Hospital for centuries have held their meetings in the Hall. It is normally open to visitors by appointment.

External paintings of biblical scenes and miniatures of Edward VI and Sir John Mason are over Long Alley's central porch; of six almswomen over the south porch and the large painting of Abingdon market cross, set high on the river end of the almshouse, were also completed by Strong in 1605 to 1607. The Charity acknowledges a grant from the Vale of the White Horse Joint Environmental Trust towards the cost of restoration of Sampson Strong's external paintings, 2002.