Main Tower

Frankfurt has the only real skyline in Germany, and this is the building that lets you stand in the middle of it. The Main Tower reaches 200 meters, about 656 feet, or 787 feet if you count the antenna, and the open-air observation deck near the top sits at roughly 650 feet. On a clear day you can see the Taunus hills to the north, the Main winding east to west, and the cathedral tower looking surprisingly small below you.

It is the only skyscraper in the city with unrestricted public access, which is why it shows up on every Frankfurt itinerary, especially for travelers on a layover from FRA who have four or five hours to spend downtown. Named for the river, the tower was completed in 1999. A cocktail bar and a restaurant occupy the upper floors, so you can trade the wind on the deck for a table with the same view.

The engineering is worth a minute of your attention. This was the first high-rise in Europe with a fully glazed facade, which is only possible because the vertical load is carried by the core and the exterior columns rather than by the walls. The building weighs more than 200,000 tons, roughly twenty times the Eiffel Tower, and sits on 112 foundation piles driven 50 meters into the ground. During construction a new floor went up every four days.

All 2,550 windows can be opened outward parallel to the facade, which is why the building needs no full air conditioning system. They close automatically when wind speed passes 70 kilometers per hour, about 43 miles per hour, or when the temperature drops below five degrees Celsius, about 41 degrees Fahrenheit.

The lobby doubles as a gallery. Helaba, the state bank headquartered here, has collected contemporary art since 1996 and commissions work tied to the architecture. The video installation The World of Appearances by American artist Bill Viola and Stephan Huber's wall mosaic Frankfurter Treppe are both in the foyer and free to see.

Two practical notes. The last elevator to the deck leaves 30 minutes before closing, and the platform shuts in bad weather or high wind, so check the tower's website before you make the trip. Once a year in May, during Frankfurt's skyscraper festival, at least 18 high-rises open to the public free of charge, and the Main Tower takes part.