The Fouilles archéologiques à Khostia en Boéotie (FaKB) project ran from 1980-1983 under the guidance of project director John M. Fossey (McGill University). The site consisted of an acropolis, two towers of a city wall, and, to the south, an industrial sector. The project identified that Khostia appears to have been discontinuously occupied from the Middle Neolithic period onwards, with site activity greatly intensifying in the later Classical period, seen through fortifications built around the acropolis and lower city, which were in use until the Hellenistic period, at which point the site was destroyed and abandoned. Though unclear, it has been theorized that the Romans were responsible for the abandonment of the site. Several centuries later, the site was once again occupied, with the walls being poorly reinforced in the 5th century CE; the final period of occupation was in the Late Roman period, and was ended by another destruction and widespread fire.
For more information, see https://portal.cig-icg.gr/node/130