Tirrenia is a frazione (parish) of Pisa, Italy with a population of 3,112 inhabitants. Immersed in the pine forest of the "Litorale Pisano" and in the coast of Ligurian Sea, Tirrenia is in the centre of the coast of Tuscany and next to the Parco Naturale Migliarino, San Rossore, Massaciuccoli, between Pisa and Livorno.

The province of Pisa is a province in the Tuscany region of Italy. Its capital is the city of Pisa. With an area of 2,448 square kilometres (945 sq mi) and a total population of 421,642, it is the second most populous and fifth largest province of Tuscany. It is subdivided into 37 comuni.