Ptuj is a city and the center of the municipality of Ptuj. It is the oldest town in Slovenia. The area of the town was inhabited already in the late Stone Age, in antiquity the Roman fort Poetovio developed from a military camp. The medieval part of the city rested on the foot of the Castle Hill. A historically important crossing over the Drava was also passed by Ptuj, where the trade route between the Baltic and Adriatic seas called the Amber Road passed.