Konstantin von Diest personally placed his train on the tracks back then—of course. “It was my baby,” he says today, 15 years later. As Head of High Speed Grinding at Vossloh Rail Services, he was responsible for developing the high-speed grinding train. And on a September evening in 2011, he sent a miniature model of that very train on its first journey at Wunderland, located in Hamburg’s historic Speicherstadt warehouse district.

Miniatur Wunderland once again demonstrated its keen eye for technological innovation. After all, the grinding train developed by Vossloh represents a revolution in the rail industry. Normally, rail maintenance machines operate only at walking speed, and rail traffic must be suspended while work is carried out. By contrast, Vossloh’s grinding train can keep pace with regular traffic at speeds of up to 80 kilometers per hour (50 mph). For example, it operates at night on the Deutsche Bahn network between freight trains, leaving behind well-maintained rails by morning.

The Vossloh grinding train also travels swiftly through the miniature worlds of Wunderland. “It was important to us that the grinding train would operate at high speed on the model railway as well,” says Konstantin von Diest. “That is our unique selling proposition.” This capability offers major benefits to rail operators: They can avoid track closures and carry out rail maintenance while services continue to run.

One of the ten “coolest trains”

On full-scale track, the grinding train removes a thin layer of material—around 0.1 millimeters—in several passes. In doing so, it eliminates tiny cracks that have formed on the hardened rail surface as a result of high speeds and heavy axle loads. This preventive treatment keeps the cracks from spreading and making an extensive, costly rail replacement necessary.

On the model, the grinding process is represented by a reddish flashing light on the underside of the miniature train. When the lighting at Wunderland is switched to “night mode,” these simulated sparks are especially easy to see. A real eye-catcher, according to Konstantin von Diest. “Whenever we visit Miniatur Wunderland, the first thing we look for is our grinding train.”

The creators of Wunderland themselves also regard it as an attraction. A video marking the 25th anniversary presents the “Top 10 Coolest Trains”—including Vossloh’s grinding train.

25 years of Miniatur Wunderland: more popular than the Eiffel Tower

Since opening in August 2001, Miniatur Wunderland has quickly become a major crowd-puller. With around 1.6 million visitors annually, it is Hamburg’s most popular attraction. In Tripadvisor’s rankings, based on traveler reviews, it is currently listed among the world’s ten most popular tourist attractions—ahead of the Eiffel Tower. “Neuschwanstein Castle in Bavaria is nothing compared with it,” says the mayor of—well, Hamburg.

With the world’s largest model railway, officially confirmed by Guinness World Records, brothers Gerrit and Frederik Braun have fulfilled a childhood dream. And in HO scale, 1:87, they face challenges similar to those encountered by full-size railways. Continuous operation also takes its toll on the small rails: material wear, metal dust, and wheel abrasion cause problems across the approximately 16-kilometer (10-mile) network. “We had to realize that we can’t outsmart physics,” Frederik Braun said in an interview for this year’s German Rail Day, “Tag der Schiene.”

That is why Wunderland also uses specialized rail maintenance equipment. Forty-eight cleaning trains with felt pads or cleaning stones keep the tracks clean, because excessive dirt interferes with the electrical current that powers the locomotives. In addition, a fleet of miniature vacuum cars is in operation, with technology that the Hamburg-based tinkerers are constantly refining.