Rotterdam
If you find yourself in Rotterdam, there's a strong chance you've arrived by water. This popular port city (the second largest in the Netherlands) has gone through an architectural renaissance since World War II, with daring, innovative structures dotting the city (cube houses!) and defining its skyline. Café culture is on the rise here, so grab yourself a table and a cup. Meanwhile, traditional cultural offerings can be found at the Boymans-van Beuningen Museum, with its paintings by Dutch and Flemish artists. And be sure to gaze upon Erasmusbrug, which is less a cable bridge than a spectacular icon, nicknamed "The Swan."