Dia (Greek: Δία), also pronounced locally as Ntia (Greek: Ντία), is an island off the northern coast of the Greek island of Crete. The island is approximately 7 nautical miles north of Heraklion. Administratively, Dia is part of the community of Elaia within the municipal unit of Gouves, Heraklion regional unit, by the municipality of Elias.
The islet looks like a giant lizard when viewed from the city of Heraklion. There is also a legend that a giant lizard tried to destroy the island of Crete, but Zeus turned it in to stone with a thunderbolt, thus creating the island.
The island is visible from Crete's capital city of Heraklion, as it would have been in the time of the Minoan kingdom, from the capital of Knossos. Because of this, it was sometimes identified as the island that Theseus escaped to after killing the Minotaur.
On Dia there are a number of protected creatures including: the snail Albinaria retusa, the lizard Podarcis erchardii schiebeli, the wild rabbit Oryctolagus cuniculus cnossius, and the eagle called mavropetritis (in the Greek language). Dia is part of the European Network of Nature (Natura) 2000 and is a vetted hunting ground. There are also a number of protected plants such as Carlina diae.