Standing proud on the left bank of the River Thames, the Palace of Westminster is one of London’s most iconic landmarks. The Gothic-style building and its towers, including the famous Elizabeth Tower, the home of Big Ben, attract more than a million visitors each year and have been immortalised by many artists over the years – Monet alone worked on 19 different paintings of the place.

But while the site’s history dates back more than 1,000 years, its ancient foundations are now at risk of falling apart.

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Ecclesiastical and monarchical buildings have been constructed on the palace’s site since at least the Middle Ages. A palace was constructed here in the first half of the 11th Century and served as a royal residence until 1512. By 1550, the House of Commons and the House of Lords already held meetings here. In 1834, a fire consumed almost the whole building and, two years later, a Royal Commission organised a competition to design a new one.

Out of 97 submissions, the one by architects Charles Barry and Augustus Pugin prevailed. They created the Gothic-style palace that exists today, which occupies a total ground area of eight acres, including courtyards and gardens. It’s nearly 300m long with about 1,100 rooms, 100 staircases and 4.8km of passageways.

But as the Brexit voting sessions have made global headlines these past few years, images of the palace and its deteriorating conditions have travelled across the world: in 2019, a House of Commons sitting had to be suspended due to a leaky roof. The cast-iron tiled roofs have never undergone major renovation or repair in more than 160 years and the leaking can also damage the interiors of the building. However, that is not the only issue the palace faces.

In 2012, the Houses of Commons and Lords commissioned a study on the condition of the palace, which indicated the need for major restoration work. The current sewage system was installed in 1888; there are more than 1,000 areas that contain asbestos; the chambers are not wheelchair accessible; and even rodents populate the place. Part of the building’s mechanical and electrical systems were installed after World War Two and should have been replaced in the 1980s but were not. Over the years, steam, gas and water services were built on top of each other and next to high-voltage electrical wires. And about 321km of telephone, broadcasting and sound wires need to be upgraded.

The Anston limestone used in the original construction, which was cheap and ideal for carving, began to quickly decay in the 19th Century and was only partially restored in the 1980s and ‘90s. On top of all of that, Barry and Pugin used combustible materials to decorate the palace’s interiors.

In 2017, renovations started in the Elizabeth Tower – covering it almost entirely with scaffolding and frustrating tourists who expected to see its famous clock. The work is expected to finish in 2021. However, the work on the Tower is not related to the restoration of the palace: these renovations are only expected to start in mid 2020s, with an estimated cost between £3.9bn and £6.3bn.

(Video by The BBC Travel Show; text by Luana Harumi)

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