Jail house rocks… an architectural marvel built over a prison vault

Hidden House in Clerkenwell, London, contender for Riba House of the Year, is a triumph of design ingenuity over challenging site contraintsVisitors to Hidden House, in London’s Clerkenwell, often need a little help to find it. It’s virtually invisible from three sides because it nestles into the angles of an old boundary wall that runs between back gardens and an imposing Victorian school. As owner Selim Bayer explains: “You’re walking around the wall and suddenly there&