Open House London 2018: What to see

It is often said that our capital is not the most welcoming of cities. If Parisians are lovers, Romans are chummy and Berliners are überhipsters, then Londoners are, well, a bit hostile. Add to this sanitisation, soaring rents and the ruthless greed of property developers, and to outsiders, London can seem a pretty unwelcoming place. (We know, of course, that it's the best city on the world: you just have to know where to look).

But now for the good news: for one weekend in September some of the city's most exclusive doorways and secret spaces are unlocked for you to have a good snoop around.

The Open House London Weekend has become a highlight of the design and architecture calendar. Since 1992, the not-for-profit organisation has given ordinary citizens a chance to explore their city. This year around 800 buildings fling open their doors to the public, alongside a comprehensive programme of walks, tours and talks. While access to everything is free, some buildings require pre-booking (see below). If you've got children, we recommend checking out the Open House Junior programme, which is specifically catered to budding architecture enthusiasts.

For the second consecutive year, all of London's boroughs are participating in the scheme. But with so much to see, it's worth planning in advance: download the Open House London App (for free), scour the 2018 building listings online, or buy a print programme for £8.50. In the meantime, we've handpicked a number of highlight venues that we can't wait to investigate.

For more detailed information on opening times and building listings, check the Open House website and online programme.

Open House London 2018: Buildings to pre-book or access via ticket ballot

10 Downing Street

Ever fancied snooping around the interiors and gardens of 10 Downing Street? Well, now you can. Or, at least, a lucky few can. For your chance to go behind the famous black door on 22 September, enter the 10 Downing Street Open House London 2018 ballot here. The nearest tube is Westminster.

BT Tower

At 189m tall, the BT Tower has loomed large over London for the last 53 years. A working communications hub, the BT Tower is home to a TV Networking Switching Centre, a communications transmitter and a plethora of subterranean optical fibre links. The tower was designed by architects Eric Bedford and G. R. Yeats and was designated a Grade II listed building in 2003. Closed to the public throughout the year, The BT Tower's inaugural participation in Open House London presents a rare opportunity to see behind the scenes. The nearest tube is Goodge Street.

Enter the BT Tower Open House London 2018 ballot here.

Open House London 2018: Newcomers

Bloomberg European Headquarters

'This building is designed to encourage cooperation and collaboration, and that's what makes for a successful business', says Micahel Bloomberg of his newly developed Headquarters in the heart of the City of London. Conceived by Bloomberg in collaboration with leading architect Lord Norman Foster of Foster + Partners, the new European Bloomberg Headquarters offers 1.1 million sq ft of sustainable office space and is home to around 4,000 employees. The nearest tube is Bank.

Pre-booking is required to access Blomberg European Headquarters during Open House London 2018

Royal Opera House

Following a multi-million pound refurbishment project masterminded by Stanton Williams, The Royal Opera House has unveiled its swanky new facade and its transformed foyer, Clore Studio and Linbury Theatre in time for Open House London 2018. Forming part of the Open Up project, the newly designed spaces will enhance the 'magical' experience of visiting one of the most famous Opera Houses in Europe. The nearest tube is Covent Garden.

The Royal Opera House Backstage Tour and History Tour are now unfortunately sold out.

To note: There will be no access to the main stage or auditorium.

US Embassy

The new US Embassy in Nine Elms reflects the best in contemporary design. Combining 'security and sustainability', the 12-storey glass cube exudes 'transparency, openness, equality', says architect James Timberlake. Built on a hill set back 100ft from the street, the new Embassy boasts a moat with waterfalls, solar panels and a plastic polymer exterior for energy efficiency and deep trenches for additional security. The nearest tube is Lambeth North.

Pre-booking is required to access the Royal Opera House during Open House London 2018

Aga Khan Centre

In their third project with the Imam of the Shia Ismaili Muslims, Japanese architectural firm Maki & Associates opened London’s Aga Khan Centre earlier this year. Principally designed to be an educational space, this gem in the heart of the capital has a variety of beautiful courtyards and rooftop gardens inspired by landscape design from across the Muslim world, stretching from Spain and North Africa to South Asia. These spaces are said to reflect some of the most significant philosophies of Islam: ‘openness, dialogue and respect for pluralism.’ Open Weekend tours include access to an exhibition and lecture on the centre and its design. The nearest tube is King’s Cross St. Pancras.

Open House London 2018: Returning favourites

Foreign and Commonwealth Office

Now's the time to take a tour of the Grade I listed Victorian government office buildings nestled in the heart of Westminster. The guided tour will take you through the magnificent and richly decorated Durbar Court, the former India Office council chamber, Locarno suite and Foreign Office grand staircase. Today, all the buildings around the quadrangle house the Foreign and Commonwealth Office. The rooms are all used on a daily basis by staff and visitors and are still often used for ceremonial occasions. The nearest tube is Westminster. Find out more.

The Great Barn

Dubbed the 'Cathedral of Middlesex' by Sir John Betjeman, The Great Barn was left to ruin until English Heritage splashed out a hefty £20,000 in 2011 to salvage it. The Royal manor pre-dates the Norman Conquest and was built by Winchester College in 1491 with help from the William of Wykeham endowment fund. The oak-framed Grade I listed barn is an exceptional example of medieval British carpentry and contains one of the most intact interiors of its era. According to English Heritage, this barn ranks alongside the Houses of Parliament and Westminster Abbey for its exceptional historic interest. The closest tube is Heathrow Terminal 5. Find out more.

Buddhapadipa Temple

Set in 4 acres of its own serene gardens, this is one of the only Thai style Buddhist temples outside of Asia. The outside approach through the grounds to the ornate, slender gables of the building may be surprising in Wimbledon, but the interior is something else. Built in 1980, the temple is covered with rich murals depicting the life of the Buddha. The closest tube station is Wimbledon Park. Find out more.

Royal Botanic Gardens Kew: Herbarium, Library, Art and Archives

Visit the Herbarium, Library, Art and Archives and Tropical Nursery at Kew – all of which are usually closed to the public – and have a peek at what goes on behind the scenes at one of the city's most famous (not to mention beautiful) gardens. We'd recommend making a beeline for the Herbarium, which now houses around 7 million species. The nearest station is Kew Bridge. Find out more.

Ruins of Garrison Church

If it's a nice day, the ruins of this Royal Artillery church originally built in 1873 are well worth the trek east. Despite being bombed in 1994, the church contains beautiful mosaics, which were salvaged from the elements thanks to a lottery fund granted to restore the roof. The RA barracks were here until 2007. It's also has a poignant contemporary resonance – the church is located just outside the barracks where Drummer Lee Rigby was murdered in 2013. The nearest station is Woolwich Arsenal. Find out more.

Baitful Futuh Mosque

The Baitul Futuh Mosque in south London belongs to the capital’s Ahmadiyya Muslim Community. It is the largest purpose-built mosque in Western Europe accommodating 13,000 worshippers. The building is a tasteful blend of Islamic and modern British architecture, and incorporates many of the original architectural elements of the old dairy site on which it was built in 2003. The focal point of the mosque is the hexagonal prayer hall, so take a good long look when wandering around its numerous antechambers. Although the Mosque was badly damaged in a fire in 2015, a renovation project is now in motion. The nearest station is Morden station. It’s open both days, and tours will run every 30 mins. Find out more.

For more detailed information on opening times and building listings, check the Open House website and online programme.