Larissa (ləˈrɪsə; Λάρισα, Lárisa, ˈlarisa) is the capital and largest city of the Thessaly region in Greece. It is the fifth-most populous city in Greece with a population of 148,562 in the city proper, according to the 2021 census. It is also capital of the Larissa regional unit. It is a principal agricultural centre and a national transport hub, linked by road and rail with the port of Volos, the cities of Thessaloniki and Athens. The municipality of Larissa has inhabitants, while the regional unit of Larissa reached a population of ().
Legend has it that Achilles was born here. Hippocrates, the "Father of Medicine", died here. Today, Larissa is an important commercial, transportation, educational, agricultural and industrial centre of Greece. The city straddles the Pineios river and N.-NE. of the city are the Mount Olympus and Mount Kissavos.
According to Greek mythology it is said that the city was founded by Acrisius, who was killed accidentally by his grandson, Perseus. There lived Peleus, the hero beloved by the gods, and his son Achilles.
In mythology, the nymph Larissa was a daughter of the primordial man Pelasgus.
The city of Larissa is mentioned in Book II of Iliad by Homer: "Hippothous led the tribes of Pelasgian spearsmen, who dwelt in fertile Larissa- Hippothous, and Pylaeus of the race of Mars, two sons of the Pelasgian Lethus, son of Teutamus." The Internet Classics Archive | The Iliad by Homer In this paragraph, Homer shows that the Pelasgians, Trojan allies, used to live in the city of Larissa. It is likely that this city of Larissa was different to the city that was the birthplace of Achilles. The Larissa that features as a Trojan ally in the Iliad was likely to be located in the Troad, on the other side of the Aegean Sea.
Traces of Paleolithic human settlement have been recovered from the area, but it was peripheral to areas of advanced culture. The area around Larissa was extremely fruitful; it was agriculturally important and in antiquity was known for its horses.