In terms of modern state boundaries, the basin centres on the territory of Hungary, but it also covers regions of western Slovakia (the Eastern Slovak Lowland), southeastern Poland, western Ukraine, western Romania, northern Serbia (Vojvodina), the tip of northeast Croatia (Slavonia), northeastern Slovenia, and eastern Austria. The name "Pannonian" comes from Pannonia, a province of the Roman Empire. Only the western part of the territory (the so-called Transdanubia) of modern Hungary formed part of the ancient Roman Province of Pannonia; this comprises less than 29% of modern Hungary, therefore Hungarian geographers avoid the terms "Pannonian Basin" and "Pannonian Plain".