The Oldest Fire Hydrant in New Orleans is located at the intersection of Moss Street and Grand Route St. John, near Bayou St. John. Installed in 1869, this oxidized hydrant represents a significant advancement in firefighting technology. Designed by inventor Birdsill Holly, whose U.S. patent count was second only to Thomas Edison, this hydrant allowed firefighters to position their equipment closer to fires and pump water directly from the bayou, enhancing the efficiency and effectiveness of firefighting efforts.

At the time of its installation, New Orleans lacked a public water system, and firefighting relied largely on volunteer forces using four fire engines. The introduction of Holly's hydrant marked a pivotal shift, enabling more powerful and efficient firefighting capabilities.