A facility ashore for enforcement of quarantine
A lazaretto was a quarantine station for maritime travelers and cargo. The concept of quarantine derives from the imposition of forty days (quarto) of isolation imposed by various Mediterranean powers (primarily by Venice) in the late Middle Ages to reduce the risk of the introduction of contagious disease from foreign ports (particularly from the Levant, where plague and similar diseases were frequent). Originally, the ships arriving from suspect locations were required to anchor outside the port during the quarantine period. Gradually, though, specialized facilities were erected ashore for the inspection and detention of crew and passengers suspected of carrying contagious disease or for the fumigation of suspect cargo. Two lazarettos, both on isolated islands, may still be found in the Venice Lagoon. Ruins of others are located in Ancona, Italy; Dubrovnik, Croatia; Manoel Island, Malta; Lazaretto Island and Zakynthos Island, Greece; and Fidra Island, Scotland (in the Firth of Forth). The Philadelphia Lazaretto is located on the shore of the Delaware River just west of the Philadelphia International Airport. It was the first permanent quarantine facility built in the United States. The City of Philadelphia built it following the Yellow Fever Epidemic of 1793, which killed about 10% of the populace and resulted in the temporary relocation of the federal government (then situated there). The Philadelphia Lazaretto was intended to protect the city and port not only from infectious disease, but from fear of disease and operated primarily between April and November each year, when contagious diseases were most prevalent. The Commonwealth of Pennsylvania took over operation of the Lazaretto in 1893, which ceased activities as a quarantine facility in 1895. It is now an historic site.