Given the remorseless pace of change from 1870 onwards, and the catastrophic damage inflicted during the Second World War, one might be forgiven for thinking that much of London's architectural heritage had been obliterated, and that what survived was given the coup de grace by insensitive post-war planning and architecture. But this is not the case. A wealth of treasures that the public know little about can still be found hidden behind London's inscrutable facades. In contrast to the perceived lack of concern at the loss of so much of London's heritage in the first part of the 20th century, today there is unprecedented public interest in its history and buildings and, not least, what lies behind closed doors inside the offices, institutions, clubs and private houses that so many pass every day; from the discreet grandeur of Whitehall and clubland to the fascinating subterranean spaces that lie beneath the capital. The hugely popular annual Open House London event has created access to over 750 buildings and places normally closed to the public and now attracts more than a quarter of a million visitors. London: Hidden Interiors has 180 examples which have been selected from a complete range of building types to convey the richness and diversity of London's architectural heritage, and the secrets that lie within. Each has had to earn its place, and most deserve much greater coverage than can be accorded here. The selection is an entirely personal one. It concentrates generally on the buildings and interiors that are less well known and to which the public are not normally allowed access - the hidden and the unusual, the quirky and the eccentric, although there is space too for some of the better known. A number celebrate unsung conservation successes of recent years, which deserve greater recognition.