Frankfurt, a central German city on the river Main, is a major financial hub that's home to the European Central Bank. It's the birthplace of famed writer Johann Wolfgang von Goethe, whose former home is now the Goethe House Museum. Like much of the city, it was damaged during World War II and later rebuilt. The reconstructed Altstadt (Old Town) is the site of the Römerberg, a square that hosts an annual Christmas market.