Also, villages of Bigadiç have natural thermal water reserves which contains Selenium and Sulfur.

The oldest known name of Bigadiç is ancient Greek Achyraos (Αχυράους in Ancient Greek), Latin(ized) Achyraus, renamed during the Byzantine era Pegadia (Πηγάδια), which means "springs, wells", from which it evolved to Begadia, to Begados, and eventually to the turkified name Bugadıç.

There are 80 neighbourhoods in Bigadiç District:[4] Ancient Achyraus was situated in the Roman province of Hellespontus, in the civil Diocese of Pontus.

Circa 400 it became a suffragan see of the provincial capital and metropolitan see Cyzicus, in the sway of Patriarchate of Constantinople.

[8] It is vacant, having had the following incumbents, so far of the fitting Episcopal (lowest) rank and members of Latin congregations :