Symi also transliterated Syme or Simi (Greek: Σύμη) is a Greek island and municipality. It is mountainous and includes the harbor town of Symi and its adjacent upper town Ano Symi, as well as several smaller localities, beaches, and areas of significance in history and mythology. Symi is part of the Rhodes regional unit.
The shipbuilding and sponge industries were substantial on the island and, while at their peak near the end of the 19th century, the population reached 22,500. Symi's main industry is now tourism and the population has declined to 2,500.
In Greek mythology, Symi is reputed to be the birthplace of the Charites and to take its name from the nymph Syme (in antiquity the island was known as Aigli and Metapontis), though Pliny the Elder and some later writers claimed it came from the word scimmia meaning a monkey.
In Homer's Iliad the island is mentioned as the domain of King Nireus, who fought in the Trojan War on the side of the Greeks. Thucydides writes that during the Peloponnesian War there was a Battle of Syme near the island in January, 411 BC, in which an unspecified number of Spartan ships defeated a squadron of Athenian vessels. Little is known of the island until the 14th century, but archaeological evidence indicates it was continuously inhabited, and ruins of citadels suggest it was an important location.