start in front of Aachen Cathedral to begin a 2-hour tour of this spectacular German city that sits on the border with Belgium and the Netherlands. Start by admiring the magnificent cathedral, one of the first monuments in Germany to be listed as a World Heritage Site. During the guided tour, find out fascinating information about the city's history, such as the reason why Emperor Charlemagne chose Aachen as his place of residence and how it became a symbol of European power. Visit important places in the city center such as the Marktplatz, Aachen's market square where you'll enjoy a vibrant university atmosphere and bustling terraces. Here, you'll also see the Rathaus, the Town Hall building that dates back to the 14th century. Afterwards, head to the Ponttor, one of the only remaining gates of Aachen's ancient defensive walls. What's more, discover the city's Roman ruins and the Elisenbrunnen building, an ancient Roman spa-bath.