Open House London is the capital's biggest architectural festival and will see 600 buildings welcome in the public totally free of charge.

It is organised to give people the chance to experience buildings "in the flesh" and learn more about architecture, engineering and design.

The buildings this year include everything from private residences and slick contemporary homes to pre-fab and social housing, as well as historically important properties.

Ambassadors' residences, private clubs, City banks and Government buildings are all on the list, and architects will be at some sites to impart their knowledge to visitors.

Open House's founding director, Victoria Thornton, said: "Experiencing a building in the flesh - inside and out, can help you understand it and assess it in a way you never could from a picture."

Detail from: http://www.londonopenhouse.org/