The borders between Gdansk, Gdynia, and Sopot aren’t well-defined. Perhaps that’s why its inhabitants like to talk about Trójmiasto, the tri-city.

Located in northern Poland on the shores of Gdansk Bay on the Baltic Sea, this city with three names has become one of the most dynamic metropolitan areas in Poland, with a population of over a million inhabitants.

Not long ago, however, the citizens of Gdansk, Gdynia, and Sopot felt that it was missing something to truly become a great city. There wasn’t a space for massive sporting events or big concerts. When international artists came to Poland, they rarely went far north. All that changed with the inauguration of the Ergo Arena.

This sports and entertainment palace, built by Ferrovial’s subsidiary Budimex, is located right on one of those blurry boundaries between Gdansk and Sopot, right in the heart of the metropolitan area. The covered stadium has a capacity of 11,500 for sporting events and over 15,000 for cultural shows.

The building rises 30 meters above the ground near the Gdansk Bay, housing more than four hectares of usable spaces. Its construction, which was finished in 2010, used more than 2,000 tons of steel and 750 kilometers of wiring. All this, among other things, made it possible to equip the Ergo Arena with one of the most advanced sound and light installations in Poland.

Shortly after it opened, the sports palace received its first major visitor. Lady Gaga hit the tri-city as part of her Monster Ball Tour. After her came dozens of other top-level artists and sports competitions. Today, the residents of Trójmiasto have one more reason to feel like they’re part of a great metropolis.