Thessaly is a traditional geographical region of Greece, comprising most of the ancient region of the same name. Before the Greek Dark Ages, Thessaly was known as Aeolia, and appears thus in Homer’s Odyssey.
Thessaly became part of the modern Greek state in 1881, after four and a half centuries of Ottoman rule. The capital of the periphery is Larissa. Thessaly lies in central Greece and borders the regions of Macedonia on the north, Epirus on the west, Central Greece on the south and the Aegean Sea on the east. The Thessaly Periphery also includes the Sporades islands.
Thessaly occupies the east side of the Pindus watershed, extending south of Macedonia to the Aegean Sea. The northern tier of Thessaly is defined by a generally southwest-northeast spur of the Pindus range that includes Mount Olympus, close to the Macedonian border. Within that broken spur of mountains are several basins and river valleys. The easternmost extremity of the spur extends southeastward from Mt. Olympus along the Aegean coast, terminating in the Magnesia Peninsula that envelops the Pagasetic Gulf (also called the Gulf of Volos), and forms an inlet of the Aegean Sea. Thessaly’s major river, the Pineios, flows eastward from the central Pindus Range just south of the spur, emptying into the Thermaic Gulf.