Poseidium or Poseidion ( Ancient Greek: Ποσείδιον) was a town on the northeast coast of ancient Euboea. It belonged to the Delian League since it appears in the taxation registry of Athens of the year 425/4 BCE, where it had to pay a phoros of 100 drachmae. [1] In the 2nd century BCE, Poseidium appears in another inscription where it had become a deme of Oreus. [2] [3]
Its site is located near the Palaiokastro ("old fort/castle") of Vasilika. [4] [5]
38°58′21″N 23°22′00″E / 38.972412°N 23.366608°E