Het Steen is the oldest building in Antwerp, and for five years it has also been the city’s front door. Since it reopened in October 2021 as a visitor centre, more than two million people have walked in from the Steenplein, about 45 per cent more than the city had forecast, and roughly two in three of them came from abroad. The building they enter dates from between 1200 and 1225. The wing they walk into dates from 2021, and before it opened 22,000 people had signed a petition to have it pulled down.

A gate, a prison, a museum

There was a settlement and a fortified keep on this bend of the Scheldt in the Carolingian period; the city’s own timeline starts with a first refuge in 850, and the first defences may have been a response to Viking raids. What survives was built in the early 13th century as the gateway to a much larger castle of the Dukes of Brabant. Emperor Charles V had it substantially rebuilt, and the name Het Steen, simply “the stone”, dates from around 1520.

For most of its life it was a prison, from 1303 to 1827. In the 19th century the city straightened the quays to stop the Scheldt silting up, and most of the fortress and the streets around it were demolished, which is why the gatehouse now stands on its own by the water. It also received a neo-Gothic makeover. In 1890 it became the city’s museum of archaeology; in 1952 an annex was added for the museum of maritime history, with its model ships and sea charts, which moved in 2011 to the MAS, the Museum aan de Stroom on the Eilandje.

The carbuncle that won prizes

In 2016 the city held an open competition for a new use; 31 architecture firms entered. It went to noAarchitecten of Brussels, whose partners An Fonteyne, Jitse van den Berg and Philippe Viérin replaced the 1950s annex at the back with a new wing in pale brick, architectural concrete and wood, coloured to match the old stone. Work ran from 2019 to 2021, on a budget of €7.4 million before VAT and fees. The architects’ own description is unapologetic: “The new extension has strengthened the old monument; together, they have become one building.”

Antwerp was not convinced at first. By April 2021 the petition calling for the demolition of the “carbuncle” had collected those 22,000 signatures. “It’s just like a boring block of flats where nobody wants to live,” one resident told VRT. The city’s chief architect, Christian Rapp, answered in seven words: “It was the best entry of five.”

The juries disagreed with the petition. Het Steen won the Flemish heritage prize in 2022, the European Award for Architectural Heritage Intervention in 2025 and, in 2026, the Grand Prix of the Erich Mendelsohn prize in Berlin. Rapp was right and the petition was wrong, and the visitor numbers settle it: a building that gets two million people through its door in five years is doing what a medieval gate was built to do. The critics, for their part, held up the Port House by Zaha Hadid, another new shape on an old building, as the way it should have been done.

What is inside now

The new wing holds the tourist office, the Antwerp City Shop with regional products, and a terminal for river cruises, and it is free to enter. So are the upper levels and the roof terrace, which look over the river and the city’s spires. Nearly 1,000 volunteer City Hosts welcome visitors and hand out tips. The building is open 363 days a year, from 10:00 to 18:00, and director Ruud Tiebos runs it. “Five years ago we gave a building a new life,” he said in October 2026.

The one paid part is The Antwerp Story, the interactive route through the old castle rooms, which sells more than 25,000 tickets a year. It was refreshed in December 2025 by the Antwerp agency Haste: touchscreens on the building’s history from 850 onwards, tapestries by the illustrator Sam Vanallemeersch, screens on each district, dioramas of smaller museums such as the Sint-Pauluskerk and Museum De Reede, and an attic of local crafts from diamonds and beer to printing and tattooing. Adults pay €7 and children from 6 to 18 €5; under-sixes and holders of the Antwerp City Pass or Museum Pass go free. Allow about an hour and a half.

Ghent made a different choice with its castle. The Gravensteen, built in 1180 by Philip of Alsace and used over the centuries as a court, a prison, a mint and a cotton mill, was restored between 1893 and 1907 in a romantic Gothic style and is still visited as a castle. Antwerp turned its castle into the place where a visit to the city begins. “Five years ago we promised that Het Steen, like Centraal station, would become a gateway to Antwerp,” said the alderman for tourism, Koen Kennis, in October 2026. The castle now charges €7 for one route and gives the roof away.