Big Ben

Big Ben is the bell, not the tower. The 96-metre structure at the north end of the Palace of Westminster was called simply the Clock Tower until 2 June 2012, when the House of Commons voted to rename it the Elizabeth Tower for Queen Elizabeth II's Diamond Jubilee; the name Big Ben properly belongs to the 13.7-tonne Great Bell hanging in its belfry. The clock's mechanism was installed in April 1859 and first chimed on 11 July 1859. Each of the four dials measures 6.9 metres across. Exterior visible 24 hours; tower tours only on released dates. The visitor route includes unavoidable stairs and has no complete step-free circuit. Exterior visible 24 hours; tower tours only on released dates. Exterior free; tower tours use dated paid tickets. The visitor route includes unavoidable stairs and has no complete step-free circuit. Westminster Underground. Yes. Events, ceremonies, maintenance and security can change the ordinary route. No. Special tours, exhibitions and premium products use separate tickets. Exterior visible 24 hours; tower tours only on released dates. Exterior free; tower tours use dated paid tickets. The visitor route includes unavoidable stairs and has no complete step-free circuit. Westminster Underground. Exterior visible 24 hours; tower tours only on released dates. Exterior free; tower tours use dated paid tickets. The visitor route includes unavoidable stairs and has no complete step-free circuit. Westminster Underground. Yes. Events, ceremonies, maintenance and security can change the ordinary route. No. Special tours, exhibitions and premium products use separate tickets. Exterior visible 24 hours; tower tours only on released dates. Exterior free; tower tours use dated paid tickets. The visitor route includes unavoidable stairs and has no complete step-free circuit. Westminster Underground. Exterior visible 24 hours; tower tours only on released dates. Exterior free; tower tours use dated paid tickets. The visitor route includes unavoidable stairs and has no complete step-free circuit. Westminster Underground. Yes. Events, ceremonies,

The Big Ben tour is a climb. A guide takes visitors up a narrow spiral stairwell of 334 steps to the belfry where the Great Bell hangs, stopping to explain a conservation project that involved over 500 people and the traditional crafts it needed — stone masonry, glass blowing, gilding, plastering, cast iron and clock mechanics. On the way the group sees the inner workings of the clock mechanism, stands beside the bell as it strikes the hour, and steps behind the dials, each 6.9 metres in diameter, to look out through the glass. Exterior free; tower tours use dated paid tickets. Westminster Underground.

Allow one hour and forty-five minutes. That is Parliament's own figure for the whole visit: a 90-minute tour plus time at the start and end to lock away and retrieve belongings. Add the arrival requirement on top — visitors must arrive no later than 30 minutes before the start time, and the queue at Cromwell Green begins outside the building — and the block a visitor should reserve in a day's plan is closer to two and a quarter hours. The start time is strict. The visitor route includes unavoidable stairs and has no complete step-free circuit.

Exterior visible 24 hours; tower tours only on released dates. Dated closures, ceremonies, performances, weather or security notices from the operator take priority over ordinary hours. Arrive early enough to complete the public route before final admission. Follow staff directions on arrival. Follow staff directions on arrival.

Exterior free; tower tours use dated paid tickets. The base ticket excludes transport, tours, premium access, special exhibitions and independently operated activities unless explicitly listed. Carry any required identity or concession document. Follow staff directions on arrival. Follow staff directions on arrival. Follow staff directions on arrival.

Westminster Underground. Use the named entrance and station because security, separate exits and large complexes can change the practical route. Allow extra time for screening and the final walk. Follow staff directions on arrival. Follow staff directions on arrival. Follow staff directions on arrival. Follow staff directions on arrival.

The visitor route includes unavoidable stairs and has no complete step-free circuit. Exterior visible 24 hours; tower tours only on released dates. Exterior free; tower tours use dated paid tickets. The visitor route includes unavoidable stairs and has no complete step-free circuit. Historic surfaces, crowds and security remain relevant.

There are no photographs from the Big Ben tour. Cameras and mobile phones are prohibited on the tour for security reasons and go into a locker with the rest of a visitor's belongings before the climb begins, which means the clock mechanism, the view through the 6.9-metre dials and the moment beside the striking bell are all seen and none of them recorded. Exterior free; tower tours use dated paid tickets.