Hassia (or Chasia) is a mountain in northern Greece.
Hassia may also refer to: Hassia Levy-Agron, an Israeli dancer, choreographer, and educator Hassia, Grevena (or Chasia), a former municipality in Grevena regional unit, West Macedonia, Greece Hassia, Trikala (or Chasia), a former municipality in the Trikala regional unit, Thessaly, Greece\ Hassium tetroxide, via the *-ia terminology for metal oxides