Basilica of Constantine © Christian Reimer
Tourists are drawn to Germany's oldest city of Trier for a taste of ancient Rome, founded as a colonial capital under Emperor Augustus in 16 BC. The city became an important political and cultural centre, and many Roman buildings and monuments remain to be explored by visitors. The city has at least five UNESCO World Heritage Sites: St Peter's Cathedral, a remarkable 11th-century church holding several significant tombs; The Black Gate, dating back to around 180 AD; 2,000-year-old ruins of an Imperial Roman bath complex once frequented by Constantine; the Church of Our Lady, another beautiful church adjacent to the cathedral; and the Amphitheatre, dating back to the 2nd century. Nearby, the Mosel Valley is Germany's main wine region, filled with vineyards and cellars, while many love to embark on cruises down the scenic Mosel River.