Cretaquarium or Thalassocosmos is a public aquarium located near the town of Gournes in Crete, Greece, 15 km east of the city of Heraklion. It first opened its doors in December 2005 and went through a major expansion during the winter of 2008-9, when 25 new tanks were installed. The aquarium is currently operated by the Hellenic Centre for Marine Research, a public research institution. Its exhibits focus on the marine fauna of the Mediterranean region and include sea organisms from over 250 species in more than 60 tanks.
Cretaquarium is located on the site of the former USAF Iraklion Air Station.