One morning during a research trip to Berlin, I found myself on the platform at Wannsee on the city’s south-western edge, where the German capital’s suburbs began to shade into those of its neighbour, the old imperial residence-city of Potsdam.

The Wannsee is a bight on the River Havel; Berliners come here in the summertime to relax and splash about in the river’s cooling waters. But not everything about this lake has always been so cheery. Heinrich von Kleist, the great Romantic man of letters, committed suicide here in 1811 in a pact with his cancer-stricken lover, Henriette Vogel. The two sat down across from each other by the shore. Kleist shot Henriette through the heart, reloaded, and then turned the gun on himself.

Kleist was a man obsessed with logistics, with the mapping out and pre-empting of all of the possibilities in a man’s existence. His letters reveal a fixation on his ‘plan for life’ and a bewilderment at anyone who proceeded through their time on earth without one. It is this theme — the cold calculation of the direction of lives — that we see recapitulated on the Wannsee 130 years later. At the beginning of 1942, a group of senior Nazi officials met at a villa here to plan the finer logistical points of the Holocaust.

Hammering out the practical side of industrial-scale murder took less than an hour and a half. At his trial in Jerusalem years later, Adolf Eichmann painted a portrait of his colleagues (senior civil servants and SS men, more than half of whom held PhDs) jockeying to “outbid each other, as regards the demand for a final solution to the Jewish question”. The meeting was an informal, friendly occasion, characterised by “happy agreement on the part of the participants”. There was wine, brandy, a buffet, cigars, a sense of bonhomie; Eichmann recalled it as “a cozy little social gathering”. Outside, January snow fell softly on the lake.

I almost went to the villa in which the conference took place. I’ve seen it in photos: large, concrete, some faintly neoclassical touches, built during the First World War for a pharmaceutical magnate with a history of violence and fraud. It’s easy enough to find, marked as it is on the map of the local area displayed at the railway station. Its street address is 56–58 Am Großen Wannsee;  it stands right on the lake. I even started to make my way there, carefully noting down the directions and searching for the correct exit from the station. But as I made my way out, I found my heart beating faster and faster. Something stopped me.  I turned back towards the trains.

I pictured myself walking up to the villa, looking at it, standing outside it, craning my neck in search of some explanatory plaque or memorial stone. What would I do there? Take a photograph of the villa, to put in a folder on my computer, or to upload to Facebook, part of an album called something like ‘My Holiday in Berlin’? Perhaps I could Instagram it, coining some sort of witty, memorable hashtag (#banalityofevil?) to go along with my photos. What would I say to someone who asked me what I was doing there? I’ve come to see the villa where Heydrich, Eichmann, and all the other desk-murderers met to dispassionately plot the logistics of the systematic extermination of millions of human beings. Yeah, millions. Just a brief interlude in my itinerary, mind you: having done a day in Potsdam, I was hoping to squeeze in Wannsee before heading up to the Spandau Citadel before it closes for the evening. The whole idea seemed so trite, so… disrespectful, but in an abstract sense I had trouble articulating.

I react viscerally to the idea of people climbing onto the concrete stelae of the Holocaust Memorial by the Brandenburg Gate and then using the pictures in their Tinder profiles. But what is it I am reacting to? Is it sacrilege? It certainly feels that way, yet at the same time it seems perverse to suggest that acts of great cruelty can sanctify a place. It seems perverse to grant such a power to the perpetrators of these acts.

In the end I didn’t leave Wannsee station. Instead, I caught the train up to Spandau. They kept Rudolf Hess, Hitler’s deputy Führer, in a prison there for almost forty years after the end of the war. When Hess, the prison’s last inmate, finally committed suicide in 1987, the West German authorities blew the building up and built a car park over the rubble to prevent it becoming a site of neo-Nazi veneration. (One could conceive of a sort of brown-shirted Way of St James, with pilgrims following in the footsteps of the Führer and his retinue: Braunau, Linz, Landsberg, Nuremberg, etc.) They are professionals at ‘managing the past’, the Germans. They even have a characteristically breezy word for it: Vergangenheitsbewältigung.

But Hess’s Spandau wasn’t what I came to see. The Spandau Citadel is a beautifully preserved mediaeval fortress, complete with lily-choked moat and imposing stone turret. I walked around the keep. I took a picture of the statue of Albert the Bear. (One of the great attractions of Germany is that it is the sort of country whose history is dotted with figures who earned sobriquets like ‘the Bear’. ‘Albert the Degenerate’, 13th Century Margrave of Meissen, is another personal favourite.)

I felt free to enjoy myself. The violent histories of old European castles have a charming fairy-tale quality to them, after all, the stuff of romantic novels and BBC costume dramas. Perhaps human suffering becomes picturesque after a certain number of centuries have passed. Perhaps this is just the way we experience the violence of history: first as tragedy, then as holiday.