Underworld Reopened: Holborn’s Historic Spy Tunnels Become Spy Museum & World‑Deep Bar

Beneath Holborn’s streets, 100 ft underground, London is preparing one of its most thrilling new attractions. Known as the Kingsway Exchange or simply the London Tunnels, this mile-long wartime dig began life in 1940 as a deep-level bomb shelter. Completed just after the Blitz eased, it never served that purpose but instead housed secret wartime communications and later became home to Britain’s Special Operations Executive—so covert even Ian Fleming worked nearby, possibly drawing on this setting for his Q-Branch scenes.

Post-war, the site morphed into a hardened Cold War telephone exchange, connecting the first transatlantic “hotline” cable in the 1950s—peering into the centre of global communication at an incredible depth. In the 1980s, government staff unwound in a licensed bar—the deepest in the UK at about 60 m below ground. Though long closed and shrouded in legend, these tunnels are set to open to the public from 2027–28 as part of a £120–220 million redevelopment.

The plan re-imagines the space as a hybrid: part immersive spy museum, part WWII memorial, and part subterranean nightlife. Expect interactive audio-visual exhibits, scent-emitting stations, a relocated Military Intelligence Museum showcasing three centuries of espionage gear, and tribute areas honouring 40,000 Blitz victims.

At its heart lies the “deepest underground bar in the world” or at least the UK—nestled in the original staff lounge. You’ll descend via heritage lifts into vaulted tunnels with double-decker bus-height ceilings, and sip on a Vesper in what aims to be an unforgettable atmospheric experience.

Backed by private equity and led by architect WilkinsonEyre—the team behind the Battersea Power Station revamp—the attraction already holds full planning approval. They’re targeting 3 million annual visitors paying £30+ per ticket. Ambitious, sure—there are hopes this could rival the London Eye for cultural cachet.

This isn’t a sanitized walk-through. They’re preserving key original features—generators, switchboards, even some signage—from the Cold War era, mingling authenticity with 21st-century tech. Those long corridors will morph into sensory tunnels, screening immersive historical scenes. All the while, trains rumbling overhead remind you you’re deep beneath the Central Line.

Whether you’re fascinated by espionage, London’s wartime resilience, or unique bars, this subterranean revival delivers on every level. It’s part museum, part theatre, part speakeasy—wrapped in genuine history layered under modern storytelling. It invites you to explore how London protected itself, how secrets were shared, and how a bar once served communications staff in the bowels of the city.

I can’t wait to step inside, lift a drink in the shadow of real wartime tech, and feel what London felt like then. It’s immersive without gimmicks, authentic without dryness, and utterly underground.