Berliner Unterwelten

Berliner Unterwelten, which means Berlin Underworlds, is a non-profit association that researches and preserves the underground structures of the city and opens them to visitors on guided tours. Beneath Berlin lie air-raid shelters, bunkers, old tunnels, abandoned railway passages and Cold War installations, and these tours offer a rare chance to see a side of the city that most visitors never notice.

The best-known tour is Dark Worlds, which takes you into a large Second World War air-raid shelter beneath Gesundbrunnen station. Guides explain how the shelter worked, what life was like for the civilians who crowded into it during bombing raids, and how the war shaped the city above. Another tour, Subways, Bunkers, Cold War, looks at the divided city, when parts of the transport network ran beneath the border and shelters were prepared for a nuclear conflict. The Nuclear Bunker Pankstrasse tour visits a fallout shelter built into an underground station during the Cold War, and From Flak Towers to Mountains of Debris explores the remains of the huge anti-aircraft towers of the war years and the hills made from the rubble of the bombed city.

The tours suit adults and older children with an interest in history, and they give real insight into how ordinary Berliners lived through war and division. Conditions underground can be cool, damp and dimly lit, with stairs and uneven floors, so wear sturdy shoes and bring a warm layer. Some tours have age limits, photography may be restricted in places, and the sites are not generally step-free, so check the details of each tour before booking if you have mobility concerns.

Public tours run in several languages, including English, and are popular, so buy tickets in advance through the association's online ticket shop, especially at weekends and in summer. Group tours can also be booked for schools and private parties. Arrive in good time at the meeting point stated on your ticket.

The association is based at Brunnenstrasse 105, by Gesundbrunnen station, which is served by the S-Bahn ring, the U8 and regional trains. Humboldthain park, with the remains of one of the wartime flak towers, is next to the station, and the Berlin Wall Memorial on Bernauer Strasse is a short ride or a 20-minute walk to the south.