Crete is the largest and most populous of the Greek islands, the 88th largest island in the world and the fifth largest island in the Mediterranean Sea, after Sicily, Sardinia, Cyprus, and Corsica. Crete and a number of surrounding islands and islets constitute the region of Crete, one of the 13 top-level administrative units of Greece. The capital and the largest city is Heraklion. As of 2011, the region had a population of 623,065.