On an empty lot in Berlin-Mitte, a low grassy mound rises almost imperceptibly. At its edge, the crumbling remains of a bricked-up entrance slope into the dark. The hum of traffic from the Brandenburg Gate, just a few hundred metres away, is the only sound. This unremarkable patch of ground, behind the state offices of Hesse and Brandenburg, is the last visible trace of the New Reich Chancellery — the nerve centre from which Adolf Hitler’s regime planned and launched the Second World War. Below the weeds, more than a thousand square metres of bunker survive, its concrete walls and ceiling still a metre and seventy centimetres thick, a subterranean relic that has slumbered largely forgotten since 1945.

Dietmar Arnold, chairman of the Berlin Underworlds Association, was among the last to descend into the complex, in 2007. He found it in remarkably good condition: a warren of rooms that once housed Chancellery staff and, in the final weeks of the war, a military hospital. Arnold now leads the campaign to stop a Hamburg investor from demolishing roughly half the bunker to make way for a seven-storey block of 66 apartments and an office building. He wants to collaborate with the Jewish Museum Berlin to turn the space into a museum and memorial focused on the war’s end. “Destroying the last remnants of the Nazi centre of power today is absolute madness,” he told the BBC, arguing that Germany has already erased too much of its communist and Nazi past.

The dispute taps into a deep vein of German memory culture. For decades, official policy has wrestled with how to handle physical traces left by the perpetrators. The more famous Führerbunker, where Hitler and Eva Braun committed suicide, lies about 120 metres to the north. After the war, Soviet forces demolished the Chancellery above ground, and the Führerbunker itself was deliberately destroyed, filled with sand and gravel, and capped with a car park. For years, no sign marked the spot, a deliberate omission to prevent neo-Nazi pilgrimages. Only in 2006 was an information panel installed. The bunker under the Chancellery escaped that fate simply because it was less symbolically charged — until now.

Berlin’s building senator, Christian Gaebler, has given the demolition plans a green light, telling the local newspaper BZ that the city will not block much-needed housing “just to preserve a bunker that could become a place of pilgrimage.” The State Monuments Office has so far declined to list the structure, noting that Berlin already has numerous underground historical sites open to the public. Yet the State Monument Council issued an internal recommendation last year urging a formal assessment of its heritage value, describing the New Reich Chancellery as “the planning centre and starting point of World War Two” and a symbol of the regime’s “catastrophic end.”

For now, the mound remains, its grass trimmed by municipal crews, its entrance sealed. If the bulldozers come, the last physical link to the Chancellery will vanish beneath a luxury residential block, leaving only the information panel a short walk away to tell visitors what once stood there. The debate is not about whether to remember, but about what form remembrance should take — and whether a hole in the ground can carry a weight that a plaque cannot.