The 1989 Velvet Revolution that freed the Czechs from communism bequeathed to Europe a gem of a city to stand beside stalwarts such as Rome, Amsterdam and London. Not surprisingly, visitors from around the world have come in droves, and on a hot summer’s day it can feel like you’re sharing Charles Bridge with half of humanity. But even the crowds can’t take away from the spectacle of a 14th-century stone bridge, a hilltop castle and a lovely, lazy river – the Vltava – that inspired one of the most hauntingly beautiful pieces of 19th-century classical music, Smetana’s Moldau symphony.