With spring in the air and summer on its heels, it cannot be long before the return of that useful conversation oiler: "Where are you going for your holidays?" Quite an unusual answer, one that might well seize up a sticky conversation altogether, would be "Dachau". More seriously, how long does it take for a town where horrible things have happened to be free from its past? For some time after 1066, Anglo-Saxons presumably found it painful to visit Hastings, and the English must have avoided Bannockburn for a while. But spots of blood do fade, bullet holes can be filled in and places recover - prosper even, if they are attractive enough, like Normandy or Waterloo.
But Dachau has not recovered, although it is certainly picturesque. The 1,200-year-old town lies in the pleasant hills just north of Munich. Its half- timbered cottages and cobble-stoned streets lined with oak trees cluster round a hill topped by the onion-domed church of St Jakob's and the Dachau Schlob, an elegant and playful 18th- century palace. In the 19th and early 20th century, Dachau teemed with painters and poets, Rilke among them, drawing inspiration from the town and the surrounding hills and moorlands.
Now almost a million people visit Dachau every year, but it is largely the notorious death camp they come to see. Very few of them stroll the short distance into the town itself, as Timothy Ryback discovered during eight years of meticulous and fascinating research. Other sites redolent of Nazi horrors have, over the years, been scrubbed clean of the stains of their dirty past. Sightseers go to Nuremberg for its gingerbread cookies and Christmas market. Munich, once the centre of the Nazi movement, is now more famous for its Oktoberfest. Berlin stands as a symbol of unity and renaissance. Leonard Bernstein could conduct Beethoven's Ninth Symphony on the site of Hitler's Reich Chancellery. But when the Beaux-Arts trio of New York were invited to perform in the Dachau Schlob, they refused because of what had happened down the road.
Any attempt to lure the concentration camp visitors into town incites accusations of exploiting the 30,000 who died in the camp. The skin certainly prickles at the thought of the vulgar flyers that were slipped under the windscreen wipers of cars parked outside the camp in 1996: "Dear visitor, welcome to Dachau, welcome to McDonald's. Our restaurant's got 120 seats, about 40 outdoor seats and for our young guests an Indoor and Outdoor Playland. How to find us? Really simple. Just follow the picture! We're happy for your visit! Your McDonald's Restaurant, Dachau." The din of outrage that followed the distribution of these flyers was heard even at McDonald's headquarters in Chicago. A formal apology was swiftly made by the chief executive of McDonald's Germany to the head of the country's Jewish community.
The advertising technique was certainly crude; but, all the same, why shouldn't Dachau have a McDonald's? Why can't it invite foreign musicians to play at its festivals? Many Dachauers are outraged at the way their town is singled out for disapproval, and how, because of the revealing "DAH" letters on their licence plates, swastikas are carved into the bonnets of their cars all over Europe. At local football matches, children from nearby towns taunt their Dachau team-mates with cries of "Kzler", the derogatory acronym for a concentration camp inmate.
Some Dachauers take preventative measures: registering their cars in other towns, even giving birth to their children elsewhere to avoid having the three black letters stamped on to their birth certificates for ever.
At the heart of this sad, original book is one particular Dachauer, Martin Zaidenstadt, a Pole who survived the concentration camp and returned to live and work in Dachau, to share drinks in the evening with his old SS guards and now, in his eighties, spend his days in the camp showing visitors around.
Ryback does not explore the reasons why Dachau remains surgically attached to its horrific past while other towns have performed successful amputations. But a pretty good explanation can be found in the person of Zaidenstadt.
At Hiroshima, My Lai and Guernica, those responsible for the destruction came from far away, did their destroying and left. In Dachau, those responsible and their descendants are still there, often living an agreeable life. This goes not only for the SS guards, but also for the civilians who colluded in the whole operation; the bakers in town today are the descendants of the bakers who, during the war, earnt not a little dough baking bread for the camp. But of the victims there is little sign.
Martin Zaidenstadt is one of the few prisoners of Dachau to have read twice the wrought-iron words above the camp's gates, "Arbeit Macht Frei" - on his way in and on his way out.