La Balize, Louisiana was a French fort and settlement near the mouth of the Mississippi River, in what later became Plaquemines Parish. The village's name meant "seamark." La Balize was historically and economically important for overseeing the river. It was rebuilt several times because of hurricane damage. The active delta lobe of the river's mouth is called the Balize Delta, after the settlement, or the Birdfoot Delta, because of its shape.

Fort Jackson is a historic masonry fort located 40 miles (64 km) up river from the mouth of the Mississippi River in Plaquemines Parish, Louisiana. It was constructed as a coastal defense of New Orleans, between 1822 and 1832, and it was a battle site during the American Civil War. It is a National Historic Landmark. It was damaged by Hurricanes Katrina and Rita, and its condition is threatened. It is marked Battery Millar on some maps, for the Endicott era work built nearby it.