DRESDEN, Germany — Last month, 74 years to the day since the bombers came, the late winter sky was gray as German tour guide Danilo Hommel called a halt before a short, dark green door in a large terracotta-roofed building that today forms part of an events and conference complex. One among several structures like it are laid out in neat rows in a bend of Germany’s River Elbe, two miles from Dresden’s historically reconstructed center.

Anonymous except for a plaque by its side reading “Schlachthof 5,” and underneath, in English, “Slaughterhouse-Five,” it was an exit-way through which the tall, lean 22-year-old prisoner of war Kurt Vonnegut Jr. may have had to stoop to emerge into a scene that would cast a shadow over the rest of his life. In February 1945, after sheltering in a deep underground meat locker in the abattoir-turned-P.O.W. camp, he and other American soldiers captured at the Battle of the Bulge, before being shipped eastward by train, were confronted by a smoldering hellscape where the Saxon capital had stood, its baroque architecture until now pristinely untouched by the wrecking hand of war.

Claiming around 25,000 lives late in World War II, the Allied firebombing raids on Dresden whipped up an inferno so fierce it sucked the oxygen from all but the most subterranean of shelters and destroyed practically everything that would burn. Vonnegut would later compare the sound of bombs stomping across the earth overhead to the footsteps of giants. Put to work by his German captors disinterring corpses from the rubble, he would one day write with characteristic black comedy that the hideous task resembled “a terribly elaborate Easter egg hunt.”