Church designs at the time differed between the North of England, which are narrow with square ended chancels, rather than the apses of the south. In Northumbria the early development of Christianity was influenced by the Irish mission, important churches being built in timber. Masonry churches became prominent from the late 7th century with the foundations of Wilfrid at Ripon and Hexham, and of Benedict Biscop at Monkwearmouth-Jarrow. These buildings had long naves and small rectangular chancels; porticus sometimes surrounded the naves. Elaborate crypts are a feature of Wilfrid's buildings. The best preserved early Northumbrian church is Escomb Church.