The patron saint of Castellammare di Stabia is Saint Catellus, bishop of the diocese of Stabia who lived in the 7th century, celebrated on 19 January; he is also co-patron, together with Saint Antoninus of Sorrento, of the archdiocese of Sorrento-Castellammare di Stabia. The town's main church is the co-cathedral of the Most Holy Mary of the Assumption and San Catello, whose building works began in 1587 and which was solemnly consecrated only in 1893, though already in use from 1643: inside, among the five chapels opening onto the side aisles, the one dedicated to the patron holds an early Christian sarcophagus used as an altar, along with archaeological finds and Roman-era structures uncovered precisely during the chapel's construction works in 1875.
The Arco di San Catello, dating from the 14th century and today among the town's symbols, is in fact not a town gate but an arch of the old cathedral, topped by a statue of the saint. Castellammare di Stabia is also known for its Antiche Terme, opened in 1836 to a design by architect Catello Troiano, and for its shipyard founded in 1783, Italy's oldest industry and the country's longest-running shipyard, still active today, together with those of Ancona and Palermo, in the construction of passenger transport ships.
