Spanish Fort, Colonial fortress at Lake Pontchartrain, New Orleans, US

Spanish Fort, also called Old Spanish Fort, Fort St. Jean and Fort St. John, is a historic site at the Lake Pontchartrain end of Bayou St. John in New Orleans. The first small fort was erected by the French in 1701; after Louisiana passed to Spain, a larger brick fort known as San Juan del Bayou was built on the site of the neglected French fortification. Its brick ruin stands along the upper side of the bayou, just back from Allen Toussaint Boulevard, beside the Floral Park section of Lake Vista.

French troops built an initial fortification in 1701 to protect trade routes to the young colony. Spanish authorities later replaced it with a larger brick structure named San Juan del Bayou, before the stronghold lost its military function in the early 19th century.

The name comes from Spanish colonial rule when the stronghold guarded the entrance to Bayou St. John. During the late 19th century the site became a social gathering place with restaurants and dance halls where early jazz performers played.

The brick ruin of the fort stands along the upper side of Bayou St. John, just back from Allen Toussaint Boulevard, beside the Floral Park section of Lake Vista. The site became a public park in 1938, after land reclamation pushed the Lake Pontchartrain shoreline out past the old fort. Look for the remnant brickwork near the bayou bank.

An iron submarine, believed to be the Confederate vessel Pioneer, was displayed in the park between 1880 and 1908 as an attraction. The craft drew onlookers at the time before it was removed, and its exact history still raises questions today.