Heraklion (Greek: Ηράκλειο, Irakleio) is the largest city and the administrative capital of the island of Crete. It is the fourth largest city in Greece.

According to the results of the 2011 census, the population of the city proper was 140,730 inhabitants, the municipality's was 173,993 while the Heraklion urban area has a population of 225,574[citation needed] and it extends over an area of 684.3 km2 (264.2 sq mi).

Heraklion is the capital of Heraklion regional unit.

The Bronze Age palace of Knossos, also known as the Palace of Minos, is located nearby.

The Arab raiders from Andalusia (Iberia) who founded the Emirate of Crete moved the island's capital from Gortyna to a new castle they called ??? ?????? rab? al-?andaq 'Castle of the Moat' in the 820s. This was hellenized as Χάνδαξ (Khandax) or Χάνδακας (Khandakas) and Latinized as Candia, which was taken into other European languages: in Italian and Latin as Candia, in French as Candie, in English as Candy, all of which could refer to the island of Crete as a whole as well as to the city alone; the Ottoman name was Kandiye.

After the Byzantine reconquest, the city was locally known as Megalo Kastro (Μεγάλο Κάστρο,[citation needed] 'Big Castle' in Greek) or Castro and its inhabitants were called Kastrinoi or Castrini ('castle-dwellers' in Greek).

The ancient name Ηράκλειον was revived in the 19th century and comes from the nearby Roman port of Heracleum ("Heracles's city"), whose exact location is unknown. English usage formerly preferred the classicizing transliterations "Heraklion" or "Heraclion", but the form "Iraklion" is becoming more common.