Ermoupoli, also known by the formal older name Ermoupolis or Hermoupolis, is a town and former municipality on the island of Syros, in the Cyclades, Greece. Since the 2011 local government reform, it is part of the municipality Syros-Ermoupoli, of which it is the seat and a municipal unit. It is also the capital of the South Aegean region. The municipal …Ermoupoli, also known by the formal older name Ermoupolis or Hermoupolis, is a town and former municipality on the island of Syros, in the Cyclades, Greece. Since the 2011 local government reform, it is part of the municipality Syros-Ermoupoli, of which it is the seat and a municipal unit. It is also the capital of the South Aegean region. The municipal unit has an area of 11.18 km².