poseidonia

{{Short description|Municipal unit in Greece}}

{{hatnote|Poseidonia is also the ancient Greek name of Paestum. In the myth "The Gift of Athena", Poseidonia is a candidate name for Athens.}}

{{Infobox Greek Dimos

|name = Poseidonia

|name_local = Ποσειδωνία

|type = municipal unit

|image_map = DE Posidonias.svg

|map_caption = Location within the regional unit

|periph = South Aegean

|periphunit = Syros

|municipality = Syros-Ermoupoli

|pop_municunit = 4114

|pop_community = 967

|population_as_of = 2021

|area_municunit = 23.7

|elevation =

|coordinates = {{coord|37|23|N|24|53|E|format=dms|display=inline,title}}

|postal_code =

|area_code =

|licence = EM

|mayor =

|website =

|image_skyline =

|caption_skyline =

|party =

|since =

}}

Poseidonia ({{langx|el|Ποσειδωνία|Posidonía}}, named after Poseidon) is a village and a 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 a municipal unit.{{Cite web|url=http://www.et.gr/idocs-nph/search/pdfViewerForm.html?args=5C7QrtC22wGYK2xFpSwMnXdtvSoClrL81-32jgAMSfbnMRVjyfnPUeJInJ48_97uHrMts-zFzeyCiBSQOpYnT00MHhcXFRTsb2fGphpq4MKX2ZkaHobySNnvZCNHXvYVvlf80XevW0Q.|title=ΦΕΚ B 1292/2010, Kallikratis reform municipalities|language=el|publisher=Government Gazette}} The population was 4,114 inhabitants at the 2021 census, and the land area is 23.705 km².{{cite web|url=http://dlib.statistics.gr/Book/GRESYE_02_0101_00098%20.pdf|publisher=National Statistical Service of Greece|title=Population & housing census 2001 (incl. area and average elevation)|language=el}} The municipal unit shares the island of Syros with the municipal units of Ano Syros and Ermoupoli. It is also known as Dellagrazia (name taken from a small church of Maria della Grazia).