The Macellum of Pozzuoli
was the macellum or market building of the Roman colony of Puteoli, now known as Pozzuoli. When first excavated in the 18th century, the discovery of a statue of Serapis led to the building being mis-identified 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.
The city of Dicearchia, founded by Greek refugees escaping dictatorship on Samos, was integrated into the Roman Empire as the city of Puteoli in 194 BC. The macellum or food market was built between the late first and early second century AD, and restored during the third century AD under the Severan dynasty.
The building was in the form of an arcaded square courtyard, surrounded by two-storey buildings. Shops lined the marble floored colonnade forming an arcade with 34 grey granite columns. The main entrance and vestibule were positioned on a main axis, which lined up across a tholos in the centre of the square to the exedra for worship which had a portico formed by four large cipollino marble columns.