Ptuj is a town in northeastern Slovenia that is the seat of the Municipality of Ptuj. Ptuj, the oldest recorded city in Slovenia, has been inhabited since the late Stone Age and developed from a Roman military fort. Ptuj was located at a strategically important crossing of the Drava River, along a prehistoric trade route between the Baltic Sea and the Adriatic. Traditionally the area was part of the Styria region and became part of the Austria-Hungarian Empire. In the early 20th century the majority of the residents were ethnic Germans, but today the population is largely Slovene. Residents of Ptuj are known as Ptujčani in Slovene.