The London region is the only place in England where we can be confident a fully-developed Romanesque style of architecture was established before the Norman Conquest: at Westminster Abbey, begun in the late 1040s or c. 1050. This chapter examines the late 11th-century phenomenon with special reference to Old St Paul’s Cathedral, but considering also the probably contemporary church of St Mary le Bow and the somewhat earlier works of Bermondsey Priory and the Tower of London. The most impressive late 11th-century monument to survive in London is undoubtedly the White Tower, the construction of which seems to have been under the supervision of Gundulf, a protégé of Archbishop Lanfranc. The most complete ecclesiastical building to survive in London from the last two decades of the 11th century is the crypt of St Mary le Bow; and, having examined the better dated but less well preserved monuments, it is opportune to try to relate this building to them.