Bombed in WWII and rebuilt with ambition—Markthal, Cube Houses, and Erasmus Bridge define a different Dutch aesthetic. Metro and tram are efficient; bikes are everywhere.
Kapsalon, international food at the Markthal, and a strong craft-beer scene. Less touristy than Amsterdam, with more space and lower prices.
Use TopTenAtlas for food, stays, and day trips (Kinderdijk, Delft). Rotterdam rewards travelers who want architecture and port energy, not only canals and museums.