Arsinoi is a Local Community (Topikē Koinotēta) of the Municipal Unit (Dēmotikē Enotēta), Ithomi

Ithomi

Ithomi may refer to several places in Greece:*Ithomi, Karditsa, a Municipal Unit in the Mouzaki Municipality*Ithomi, Messenia, a Municipal Unit in the Messenia Regional Unit...

, of the municipality

Communities and Municipalities of Greece

For the new municipalities of Greece see the Kallikratis ProgrammeThe municipalities and communities of Greece are one of several levels of government within the organizational structure of that country. Thirteen regions called peripheries form the largest unit of government beneath the State. ...

 (Dēmos) of Messini

Messini

Messini is a Municipal Unit and Seat of the municipality of Messini within the Regional Unit of Messenia in the Region of Peloponnēsos, one of 7 Regions into which the Hellenic Republic has been divided by the Kallikratis plan, authorized by Law 3852, Issue 1 of 7 June 2010 and Issue 2 of 11...

 within the Regional Unit (Perifereiskē Enotēta) of Messenia

Messenia

Messenia is a regional unit in the southwestern part of the Peloponnese region, one of 13 regions into which Greece has been divided by the Kallikratis plan, implemented 1 January 2011...

 in the Region (Periferaia) of Peloponnēsos, one of 7 Regions into which the Hellenic Republic

Greece

Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....

 has been divided by the Kallikratis plan, authorized by Law 3852, Issue 1 of 7 June 2010 and Issue 2 of 11 August 2010 and implemented 1 January 2011 after elections of officers in November 2010. Before 2011 it held the same position in the administrative hierarchy, according to Law 2539 of 1997, the Kapodistrias Plan, except that Ithomi was an independent deme and Arsinoi was a Local Division (Topiko Diamerisma) within it.