The Coolsingel is Rotterdam's main north–south boulevard, broad and busy, and the only stretch of the centre to give a real sense of pre-war Rotterdam — the City Hall (Stadhuis), the Beurs (old commercial exchange), and the Witte Huis at the southern end all survived 14 May 1940 more or less intact, mostly because they sat at the very edge of the bombed area.
The avenue was rebuilt as a six-lane traffic artery after the war and pedestrianised in stages after 2017. Today it is much more pleasant — wide pavements, café terraces, and a clear line of sight from City Hall down to the Maas. The Bijenkorf department store mid-way along is worth a look for its bold 1957 Marcel Breuer facade.