The Macellum of Pozzuoli was the macellum or market building of the Roman colony of Puteoli, now the city of Pozzuoli in southern Italy. When first excavated in the 18th century, the discovery of a statue of Serapis led to the building being misidentified as the city's serapeum or Temple of Serapis.
A band of borings or Gastrochaenolites left by marine Lithophaga bivalve molluscs on three standing marble columns indicated that these columns had remained upright over centuries while the site sank below sea level, then re-emerged. This puzzling feature was the subject of debate in early geology, and eventually led to the identification of bradyseism in the area, showing that the Earth's crust could be subject to gradual movement without destructive earthquakes.