Early nineteenth-century London is often seen as the architecturally poor cousin of other European cities. The backward glance of the historian presents a story of unrealized urban visions and abandoned grand projects rather than focusing on what was actually achieved and built. Contemporaries viewed things differently; London was ‘the new Rome’, the first city of a new Empire, and the new classical architecture and urban planning made reference to its ancient counterpart. The nostalgia for a temporally distant Rome was predicated on the invented memory of its architectural splendours. But ancient Rome was in ruins. For London to equal the status of Rome would it too need to become a ruin? Did its future lie in fragments?