Going underground: exploring the best sights below London

Sick of scratching the surface of the city? Forget the tube: from catacombs and abandoned stations to lost rivers and buried art-hubs, it’s possible to explore London’s real underground. Here's our guide to the best sights and how to reach them.

From glimpses of another world, like the woolly mammoth that once wandered around Canary Wharf, to sobering reminders – imagine the sheer fear of following the masses down to the tube shelters as bomb sirens went off above you during WWII – London’s underground spaces represent a layered tapestry of its history. War, death, plagues, hide-outs and adventure: you’ll find them all beneath modern-day London.

Ride the postal railway

Back in Victorian London, the Post Office had a problem. Millions of letters to deliver, but increasingly crowded streets slowing things down. The solution? An underground rail system that air-blasted mail across the capital on tiny cars.

It was a hit, and not only for post: operators often had to turn down requests for a ride from men on their way home from the pubs near Euston, where the ride began.

In 1927, the system was upgraded to become the world’s first driverless electric railway, trundling 6.5 miles underneath London and linking sorting offices and postal depots from Paddington to Whitechapel.

The line stopped running in 2003, but in 2017, for the first time ever, Mail Rail is opening up to the public. From mid-2017, visitors will be able to take a 15-minute ride through a 1km stretch of the tunnels on a specially-built passenger train, as part of the new Postal Museum. Keep an eye on the website (postalmuseum.org) to find out when it's full steam ahead.

Catacombs and the Magnificent Seven

The Victorians didn’t just have problems with the post. There were too many people – and thus too many dead bodies – in London. Parish churchyards could no longer cope, and so seven large, purpose-built cemeteries were established between 1832 and 1841. Each burial ground now houses around 250,000 souls.

Highgate Cemetery, eternal home of Karl Marx and George Eliot, is the most famous of the ‘Magnificent Seven’, and all of them are atmospheric places. But if you’re after something really spooky, Kensal Green, West Norwood, Brompton and Highgate itself – although its offering is above ground – boast catacombs.

West Norwood and Brompton are the easiest to visit: at West Norwood, you can book a tour (fownc.org; you’ll also have to become a ‘Friend’ of the cemetery for a small fee), and Brompton runs around four catacomb open days a year, when you can tour the atmospheric burial chambers for around £5 (brompton-cemetery.org.uk). You’ll see forbidding cast-iron doors (used in Guy Ritchie’s 2009 Sherlock Holmes), crumbling wooden coffins, and touching floral tributes from the 1800s, now rotted down to yellowing twigs.

Ghost stations

Although London Underground itself may be pretty workaday, there’s something thrilling about an abandoned station, and London has a surprisingly large number of ‘ghost’ stations that used to operate as part of the network but are now unused.

Getting access to them can be difficult, but the London Transport Museum runs ‘Hidden London’ tours (ltmuseum.co.uk) taking in stations including Down Street (the Mayfair bunker where Winston Churchill sheltered during the Blitz), Euston (whose disused tunnels hold vintage posters), Clapham South (still operational, but with secret areas that were used during WWII) and Highgate (which is slowly being reclaimed by nature). Tickets go fast, but you can sign up to the museum's newsletter to help ensure you’re quick off the mark and can enjoy the eerily empty corridors and platforms.

Art in the tunnels

From a weekly life-drawing class to a full-blown immersive adventure in Alice's Wonderland, the Vaults, underneath Waterloo station (thevaults.london), has stepped things up a notch for London’s arts venues, subterranean or otherwise.

The curators always have surprises in store for visitors to this network of bricked archways and tunnels, such as an underground lake you can punt across and an underworld where confessing your sins could save your soul.

There are also bars to wet your whistle (your mouth might be dry from hanging open while gaping at the glowing lights, mind-bending costumes, and out-there performances). Even the entrance is pretty cool – through the Leake Street Graffiti Tunnel.

Lost rivers

Sure, there’s the Thames, but have you heard of the Fleet or the Tyburn? These lost rivers still flow beneath London and can be glimpsed, heard, and even smelled, rushing past under your feet, at various locations in the capital.

Head to Gray’s Antiques (graysantiques.com) on Davies St in Mayfair to see the Tyburn (and fish!) gushing through the basement. Staff will be happy to point you in the right direction. The Fleet, meanwhile, makes an appearance in a grate in the middle of the (quiet) road outside the Coach & Horses on Ray St in Clerkenwell – sadly, the pub has now shut.

If you want more tips for hunting the rivers, and other fascinating facts, join a relaxed walking tour led by Paul Talling (derelictlondon.com), an author and guide who leads walks (above ground!) down the valleys of the rivers.

Walking under water

While London has had a lot of tram and foot tunnels, most are now closed or in use by trains. Thankfully, the well preserved Greenwich Foot Tunnel is still going strong.

It runs underneath the Thames, from right next to the restored Cutty Sark ship, and represents a pretty amazing feat of engineering for its time. It was built in 1902 to help people reach their workplaces in London’s Docklands, and you can still walk and even take your bike (you’ll have to push it at busy times) the length of the tunnel, which is made of cast-iron and concrete and runs for 370m.

Its yellow-lit length has a strangely sci-fi feel, and thinking about the tonnes of water flowing above you adds to the sense of everyday adventure of a trip deep beneath the river. Since refurbishment, the lifts generally work for the tunnel’s entire 24-hour opening period, which is good because otherwise there are 100 stairs to climb at each end.

War bunkers

One of London’s more famous underground spaces, the Churchill War Rooms in Westminster was once a top-secret wartime hideaway, quarried from a government basement and protected by ‘the Slab’, a massive layer of concrete 1.5m thick in places.

Nowadays, tourists roam around the underground bunker that sheltered Winston Churchill and his team as they plotted victory while bombs fell on London. But the bunker’s past lingers in the air: the Map Room has remained exactly as it was left on the day the lights were switched off in 1945.

The relics of Crossrail

Like the city above, the land beneath London never stands still: areas are filled in, closed off, opened up and explored. Massive engineering projects in recent years have exposed whole layers of the city’s past.

An exhibition at the Museum of London Docklands, Tunnel: the archaeology of Crossrail, shows off everything from skulls unearthed in plague pits to a mammoth tooth, from chamber pots to a 55-million year old piece of amber. These artefacts were unearthed by the excavations for the Elizabeth Line (Crossrail), which involved the digging of 26 miles of tunnels and will cut through the heart of London on its way between Heathrow and Essex from 2019. The exhibition (museumoflondon.org.uk) runs until September 2017.