Elymnio (Greek: Ελύμνιο, older form Ελύμνιον) was an ancient city of Euboea, in which today is known only from written documents and sources. The correct location is not known, it is said it is located near modern Limni by the coast of the North Evian Gulf. This name of this ancient city has brought the name to a modern municipality of Elymnioi of which the seat of the municipality is in Limni.