(spatium vel via processionum a retro altaris; latus pone chorum; Fr. partour de chaeur, i.e. behind a choir). The transverse aisle in square- ended churches is commonly doubled, as at Lichfield, or even tripled, as at Winchester and at St. Mary Overge, in order to provide room for chapels as well as a passage for processions. At Hereford this aisle resembles a low transept. The eastern screens at Fountains, the Lady chapel of Hexham, and the Nine Altars of Durham seem to have been further developments of the same idea, which appears also in the longitudinal new walk of Peterborough. At Canterbury, pilgrims to the martyrdom passed up the south aisle of the nave, and through the passage under the platform of the crossing.