Standing more than seven feet tall in its bronze court shoes, Antony Dufort’s statue of Margaret Thatcher makes an imposing welcome to the House of Commons. That wagging finger still has the power to chill, even if the legendary handbag has been replaced by a sheaf of notes.

As MPs head off for their summer recess – perhaps a prudent break in Worthing instead of Tuscany this year – the Houses of Parliament are opened to the public, and this summer the recently unveiled Iron Lady is expected to be number one attraction.

Half a million visitors have taken the Palace of Westminster tour in the seven years since summer opening became a fixture of the parliamentary calendar.

Led by dedicated guides, the 75-minute journey takes visitors through the Queen’s Robing Room, the Royal Gallery, Peers’ Lobby, Central Lobby, Members’ Lobby, and St Stephen’s Hall, followed by the Commons chamber and the House of Lords, and finally the newly restored Westminster Hall.

The Commons chamber always comes as a surprise to visitors who see it for the first time. We’re accustomed to televised images of MPs shouting, booing and waving their papers at each other, but nothing really prepares you for the intimate size of the room. It’s much smaller and more personal than it looks on television, and standing in the narrow space between the front benches is a quite new take on opposition politics.

At 900 years old, Westminster Hall is one of the most atmospheric spaces in London. Although it has been altered and restored over the years, the walls of this huge arched room are still those built by William Rufus in 1097. The great trials of state were held here - Thomas More, Charles I and the Gunpowder Plotters – and this is where the public have queued in thousands to pay their respects to monarchs lying in state.

Neither the fire of 1834 nor the Blitz managed to dent it, so it seems a pity that the Hall is currently occupied by an incongruous prefab structure, built to display an exhibition about the abolition of slavery. Fascinating though this is, I can’t believe there wasn’t somewhere else in the Parliament buildings to host it. At least the partitions have been constructed so that they can be removed within six hours, just in case the hall is needed in a hurry for the Queen’s lying in state.

If politics and heritage are not your thing the tour is still a visual feast, and as design statements go Augustus Pugin’s Parliament is hard to beat. After years in the wilderness of taste, Pugin is undergoing a revival of interest and this is arguably his masterpiece.

When Parliament was destroyed in the 1834 fire, a competition was held among architects to rebuild it. Sir Charles Barry won the commission but he had never worked in the required gothic style and became completely dependent on Pugin, with his manic attention to detail, to give the buildings their stately, mediaeval-inspired identity.

The glorious handblocked wallpapers in crimson, azure blue and racing green could have you throwing out your Dulux Brilliant White for ever. Every door knob, curtain rail, coat hook and umbrella stand are part of a grand decorative scheme which symbolises the aspirations of a nation at the height of its powers.

The Summer Opening runs until September 29. There are no tours on Sundays or Bank Holidays.

Opening hours:

August: Mon, Tue, Fri, Sat: 9.15am - 4.30pm (Wed, Thu: 1.15pm - 4.30pm)
September: Mon, Fri, Sat; 9.15am - 4.30pm (Tue, Wed, Thu: 1.15pm - 4.30pm)

Tickets: adults £12, concessions £8, under 15s £5

Tickets available on the day at 6/7 Old Palace Yard, next to the Jewel Tower, or in advance (recommended) from 0870 906 3773 or through Keith Prowse - there are no handling or other extra charges. Groups call 020 7014 8440

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