Known more formally as the Dean’s Staircase, this spiral staircase was designed by none other than Sir Christopher Wren and provides access to the triforium in St Paul’s Cathedral.

The staircase – each step of which is embedded into the wall – was built between 1675 and 1710 in the cathedral’s south-west tower by William Kempster. The ironwork is by famed French metal worker Jean Tijou.

Located in the south-west bell tower, the stair’s 88 Portland stone steps rise some 50 feet.

The staircase, which can be seen on the cathedral’s guided tours including triforium tours, has become famous in recent years thanks to its appearance in the 2004 Harry Potter film, The Prisoner of Azkaban, as well as Guy Ritchie’s 2009 film Sherlock Holmes.

The staircase has also been the site of art installations including Antony Gormley’s Flare II – which featured a falling figure within a cloud of wire.

WHERE: St Paul’s Cathedral (nearest Tube stations are St Paul’s, Mansion House and Blackfriars); WHEN: 8.30am to 4.30pm Monday to Saturday; COST: £21 adults/£18.50 concessions/£9 children/£36 family (these are walk-up rates – online advanced and group rates are discounted); WEBSITE: www.stpauls.co.uk (for tours, head to www.stpauls.co.uk/visits/visits/guided-tours)