Marmari (Greek, Modern: Μαρμάρι, Ancient/Katharevousa -ον -on), older forms: Marmario and Marmarion is a municipality in the prefecture of Euboea, Greece in the southern and the southeastern end of the island. Marmari is linked with the road linking the GR-44 (Chalkida - Karystos). It also serves ferry routes with the mainland with the port of Rafina.