The first mention of Parlascio was in 1193. The oldest part is without a doubt the peak of the hill, where archaeological digs still underway have brought numerous fragments from the Etruscan age to light (from the 7th century BC). A few of these artefacts are viewable at Casciana Terme, in the thermal spa building. A castle once crowned the hill, some ruins of which are still standing, in addition to the unmistakable circular form which was one of the Pisan castles that fell into the hands of the Florentines in 1406.