Walking tours of Frankfurt’s Old Town typically start at the Römerberg, where the 15th-century City Hall is the star attraction. After admiring its distinctive façade and Venice-inspired Bridge of Sighs, head inside for a guided tour, including the lavish Kaisersaal (Emperor Hall), once used for coronation banquets and adorned with 19th-century portraits of the 52 Kings and Emperors of the German Holy Roman Empire. Leave yourself time to explore the rest of the square too, where the multi-colored timber-fronted buildings, the red-brick tower of the St Nicholas Church, and the looming spire of Frankfurt Cathedral afford plenty of photo opportunities.