Clapham South station and the deep shelter beneath it

Clapham South is the Northern line station on the corner of Balham Hill and Nightingale Lane, at the southern edge of the Common. Below it sits one of the stranger pieces of SW12 history: a wartime deep-level shelter you can visit on a guided tour. Tickets are advance booking only, so check the London Transport Museum site for dates before you plan anything.

The station

Charles Holden designed Clapham South, which opened on 13 September 1926 as the first station on the Morden extension of the City & South London Railway, now part of the Northern line. It sits on the Morden branch between Clapham Common and Balham, on the Zone 2/3 boundary.

Holden was recruited in the early 1920s by Frank Pick, then at the UERL, to design the stations for the extension. An Act of Parliament authorising it passed in 1923. The Morden stations used Portland stone and double-height ticket halls, and Clapham South is Grade II listed. An apartment block was added next to it in the mid-1930s. Before opening, the names Balham North and Nightingale Lane were both proposed.

Why there is a shelter underneath

After the Blitz bombing of October 1940, shallow Tube stations were no longer thought safe, and the government planned deep shelters. The idea was ten shelters for about 10,000 people each. Eight were finished, each with a capacity of 8,000, at Belsize Park, Camden Town, Chancery Lane, Goodge Street, Stockwell, Clapham North, Clapham Common and Clapham South, according to the London Transport Museum.

Each shelter had two parallel tubes, 16ft 6in across and 1,600ft long, built below the existing station tunnels and split into two levels. Depth is given as about 30 metres. Construction started in 1941. The shelters opened to the public in early July 1944, in response to V-weapon attacks, with Clapham South among them.

There are two entrances. The south one is on the west side of Balham Hill, opposite Gaskarth Road. The north one is on the Common, where Clapham Common South Side, Nightingale Lane and The Avenue meet. The Balham Hill site also held offices and ticket printing for all eight shelters, according to Subterranea Britannica. The surface building at the Balham Hill entrance is Grade II listed in its own right.

Windrush, 1948

The Empire Windrush reached Tilbury on 22 June 1948. With no accommodation for the new arrivals, the Colonial Office housed some of them in the Clapham South shelter. Sources differ on numbers, so a few hundred is the safe figure. The nearest labour exchange was on Coldharbour Lane, Brixton, so the men went looking for work there, and Subterranea Britannica says that made Brixton a focus for West Indian settlement. The Women’s Voluntary Service ran a refreshment tent on the Common near the shelter entrance that July.

In 1951 the shelter became the Festival Hotel, cheap lodging for Festival of Britain visitors, and it closed after a fire in the Goodge Street shelter. Interiors for Stephen Poliakoff’s 1988 film Hidden City were shot here too.

The tour

London Transport Museum runs “Clapham South: subterranean shelter” as part of its Hidden London programme. It is a revamped, more immersive version of the earlier tour, announced in August 2024.

• Length: 75 minutes.
• Price: £39, or £36 for concessions and children. The ticket includes half-price one-day entry to the museum within a month of the tour. Tickets are non-transferable.
• Meeting point: in front of the Marks & Spencer Food Hall on Balham Hill, SW12 9EA.
• Age: a government listing says 10 and over.
• Times: listed slots are 11:00, 13:00 and 15:00. Dates change, so check the museum site rather than assuming a tour is running.

Two guides lead it, one playing a 1940s ARP warden, following a South London family’s first night in the shelter. You walk about a mile of tunnels, including reconstructed areas such as the warden’s cabin, medical bay and canteen. Slots can sell out, so book early.

The museum also bills “Clapham South: ghosts of the Underground” as its first Hidden London Halloween tour, set in the same shelter. Many slots show as sold out. Clapham South is the only deep shelter among the museum’s 12 Hidden London tours.

Next door

The shelters sit in pairs around the Clapham stations, and Londonist says the Clapham South pair lie either side of the station. The Clapham Common shelter was leased in 2014 by Zero Carbon Food, behind the Growing Underground salad farm, whose founders are Richard Ballard and Steven Dring.

Read more on the tour at the London Transport Museum booking page, the Subterranea Britannica entry and the museum’s story of the deep-level shelters.