Boros Collection

The gray concrete giant seems out of place on the elegant Reinhardtstrasse. Expensive restaurants, hotels, booksellers, and the Berlin headquarters of the FDP (Free Democratic Party) define the surrounding cityscape.

The Reichsbahnbunker, built between 1942 and 1943 by forced laborers under the orders of Nazi authorities, was originally intended as a shelter for up to 2,500 Reichsbahn passengers. Its floor plan and exterior structure resemble a freestanding Renaissance-style palazzo; Albert Speer was involved in the planning, as the building was meant to be integrated into the "World Capital Germania" following the "Final Victory." That never came to pass.

After World War II, the bunker served a wide variety of functions, including a military prison, a clothing depot, a storage facility for tropical fruits, and—most recently—a techno and fetish club. Following its closure in 1996 due to drugs and excessive hedonism, it stood empty until 2003, when the publisher, media entrepreneur, and contemporary art collector Christian Boros acquired it and converted it into a private museum and his personal domicile.

The exhibition Boros #1 ran from 2008 to 2012 and drew 120,000 visitors, while Boros #2 (2012–2016) saw 200,000; currently, Boros #4 is on display. Contemporary works by Wolfgang Tillmans, Olafur Eliasson, Ai Weiwei, Klara Lidén, and many others have been and continue to be showcased here.

The conversion of the labyrinthine interior must have been complex and costly, lasting a full five years. Intricate breakthroughs made with diamond-tipped cutters reportedly drove the architects to despair. From 120 original shelter rooms, 80 exhibition spaces were created across five floors, covering 3,000 square meters with ceiling heights varying between 2.20 meters and 13 meters.

The interior was intentionally left in bare concrete. Relics from the Nazi era—such as "No Smoking" signs, inscriptions, directional arrows, a gas meter with a rotary dial, and the scratched steel entrance door with heavy bolts—have been preserved. Additionally, black paint remains from its days as a venue for darkrooms. On the roof, Boros had a penthouse built in the style of a Mies van der Rohe pavilion, complete with a terrace, garden, pool, and undoubtedly a fantastic view over Berlin-Mitte.

One unique aspect of this private museum is the long waiting list for a viewing; due to fire safety regulations, only 12 people can participate in a guided tour at a time. Another distinctive feature is the sheer scale and maze-like structure of the building, coupled with a lack of natural light that evokes an artistic "ghost train."

The installations, which often fill entire rooms, are a constant surprise. In some cases, sculptures break through walls, stretch across multiple rooms, and merge with the bunker to become a Gesamtkunstwerk (a total work of art). Several artists have created works specifically for this unique location. The owners treat visitors as their guests, and Karen Boros occasionally leads tours herself.

A visit is a profound experience, but also an exhausting one due to the claustrophobia of the concrete labyrinth. One breathes a sigh of relief when, after two hours, they leave the bunker behind to see the sun and breathe fresh air once more.