For 87 days in 1991 the world watched in helpless horror as 2000 civilians, and volunteers from all around Croatia, defended the town of Vukovar against tens of thousands of heavily armed soldiers from the Serbian dominated Yugoslav National Army.
The fighting had broken out in the wake of the collapse of the former Yugoslavia.
Vukovar, on the banks of the Danube, became known as "The City of Heroes" for the almost countless acts of valour among the untrained volunteer army of defenders.
Yet it also has a much darker significance.
Not only was this the first town in Europe to suffer such devastation since the Second World War, but the pattern of the indiscriminate bombardment of civilians that characterised the Yugoslav wars, was first seen here.
The siege also brought a new and terrible phrase into common usage.
The first cases of organised ethnic cleansing took place in Vukovar.
Former BBC correspondent Martin Bell, who covered the siege, returns 20 years later to find out how Vukovar and its people are recovering and finds Vukovar today is a shadow of its former self; haunted by the ghosts of 1991.
Martin Bell returns 20 years on to the Siege of Vukovar in Croatia.