"I'm no construction expert, but if you ask me, this won't be around for much longer," says Alexander Schmidt, a historian at the Documentation Center at the site of the notorious Nuremberg Rallies. Schmidt scratches the crumbling surface of the white stone steps of the grandstand designed by Hitler's favorite architect, Albert Speer.

"The city is prepared to invest, but we need help, "Schmidt tells me. "Otherwise everything will simply fall apart."

I've come to Nuremberg to look at something that should never have been and now needs rescuing: the grandstand at the Zeppelinfeld, the massive open-air space where the Nazis held their annual party rallies from 1933 to 1938. It's the only surviving, major, completed work by Speer, and it's pretty much a ruin. The façade is crumbling; grass and moss grow from the constantly expanding cracks. Various areas have had to be fenced off to preserve visitors' safety.

The structure was conceived for the ages, but no sooner was it completed than the first serious flaws became apparent. In his eagerness to copy the great architectural works of the antiquity, Schmidt tells me, Speer used shellbearing limestone, a material that's fine for Greece but that is no match for winters in Central Europe. There were already cracks in the stone in 1938, the last time Hitler stood on this grandstand to address adoring masses.

Restoring the structure would cost around 70 million euros ($97 million) - hardly a huge sum, if the federal and state governments chip in, as the Documentation Center is confident they will.

But is it okay to spend money to preserve a building whose main purpose was to glorify Hitler?

An architect's best friend

An estimated 200,000 people visit the site every year, making it one of Nuremberg's major tourist attractions, and almost all of the visitors climb up the grandstand. It's easy to understand the fascination. The total area of the site measures 140,000 square meters (1.5 million square feet), and the edge length of the surrounding walls is 270 by 380 meters (886 by 1,247 feet). An audience of 200,000 people fits inside this outdoor venue.

So much for the numbers. You first get a sense for what they mean when you stand on the spot where Hitler once glared down at his minions.

It's a bizarre feeling, simultaneously uncanny and absurd. I've seen lots of film footage of the Nuremberg Rallies, and standing in this spot right now, I find it quite easy to imagine the power of those propaganda event. I can almost hear Hitler's hysterical yelling.

On the other hand, the backstop still remains from where American GIs used to play baseball. From 1945 to 1990, the US military used the site as a so-called Soldiers' Field, and Nuremberg's American Football team still plays its games here. The Führer's dream of a thousand-year Reich ended with a bunch of Yanks throwing balls around.

Symbolism in vain

Schmidt takes me inside the building. Underneath Hitler's rostrum is a splendid foyer called the Hall of Honor, or the Hall of Gold, with a six-meter-high ceiling and elaborate golden mosaics. The idea was for Hitler to ascend to his spot on the grandstand like a savior appearing out of thin air. But Hitler preferred different symbolism. He always arrived at the Nuremberg Rallies by car and made his way as a "man of the people" through the throngs of his subordinates to the grandstand. He was never in the Hall of Gold. It wasn't the last time Speer built something completely useless.

"After the war, Speer once said that Hitler was an architect's best friend, because for him money was no object," Schmidt tells me. "They were a bit like two kids daring one another to take it one step further. In the end, they knew no limits whatsoever."

After I've inspected the Hall of Honor, Schmidt takes me to the Documentation Center, a museum opened in 2001 in the northern half of the Nazi Congress Hall. As good as the exhibit is, what impresses me most is the shear scale of the building. Construction was halted in 1939 with the start of World War II, but the structure is still 39 meters high.

If it had been completed, it would have held 50,000 people, yet it would only have been used once a year - for the annual Nazi party member conference. There's a viewing platform, seemingly suspended in the air outside the museum, where I pause to look at the monstrous hulk of a building. Rarely is Hitler's megalomania been more palpable.

The other side of the coin

A few hours later, I'm at the other end of town in a very different structure, the court building where the Allies put Speer and other leading Nazis on trial after World War II. For many Germans, the Nuremberg Trials from 1945 to 1949 were an example of the victors making the rules. But for many more people around the world, they were an event that symbolically brought down the curtain on the Third Reich and an attempt to hold horrendous criminals accountable for their actions.

"Our exhibition is in a certain sense the opposite of that at the Documentation Center," the curator Henrike Zentgraf tells me. "We have relatively few objects here, but we've got a lot of film footage and written material. A legal trial, after all, consists primarily of words."

Zentgraf is right. The main attraction, if you want to call it that, is the bench upon which Hermann Göring sat as he was cross-examined and eventually sentenced to death. Otherwise the museum is full of explanations and interactive videos that illuminate various aspects of the Nuremberg Trials.

Hands on it's not. You have to use your brain to learn from this museum. What I find most interesting are unexpected details, such as the fact that the Nuremberg Trials were the first legal proceedings to feature simultaneous interpretation and video evidence.

The final room of the exhibition is devoted to the beginnings of efforts by the international community to punish political leaders for crimes against humanity, for instance in Rwanda and former Yugoslavia. I'd never thought about the connection between the Nuremberg Trials and these later attempts to see justice done.

Thanks to the Nuremberg Rallies and the racist Nuremberg Laws, this northern Bavarian city will forever be associated with one of the darkest chapters in human history. On the other hand, Nuremberg also played a role in perhaps making the world a slightly more humane place.