In February 2017 I went to Anvers (Antwerp) for visiting a photography exhibition. I had little time left and I just pictured the Central Train Station, which is considered one of the most beautiful in Europe.
From the web: "The station is now widely regarded as the finest example of railway architecture in Belgium, although the extraordinary eclecticism of the influences on Delacenserie's design had led to a difficulty in assigning it to a particular architectural style.....In 2014 the British-American magazine Mashable awarded Antwerpen-Centraal the first place for the most beautiful railway station in the world.'

The next day, going back to Paris, I had few hours in Brussels. Walking from the Midi Train Station, I got to 'La Grand Place' in the central area of Brussels. Another gem in Europe, the Grand Place is a large area surrounded by magnificent buildings with several typical restaurants and stores. It is unique and should not be missed.
From the web: 'The Grand Place or Grote Markt is the central square of Brussels. It is surrounded by opulent guildhalls and two larger edifices, the city's Town Hall, and the Breadhouse (Maison du Roi) building containing the Museum of the City of Brussels. The square is the most important tourist destination and most memorable landmark in Brussels. It measures 68 by 110 metres, and it is a UNESCO World Heritage Site.'