Once the Siege of Port Hudson battlefield, Port Hudson State Historic Site was designated a National Historic Landmark by the U.S. Department of the Interior in 1974. Now, the historical site hosts several living history events, including the Battle of Port Hudson re-enactment held annually during the last full weekend of March in which visitors can watch authentically costumed interpreters demonstrate Civil War weapons and equipment.
When New Orleans fell to Federal troops in late April 1862, Confederate control of the Mississippi was in jeopardy. The bluffs near the small town of Port Hudson represented a perfect site for the river batteries. The Siege of Port Hudson began on May 23, 1863 and continued as the Confederates nearly exhausted their ammunition and were reduced to eating mules, horses, and rats. Surrender terms were negotiated, and on July 9, 1863, the Union army entered Port Hudson. The siege became the longest in American military history. After the siege, the garrison at Port Hudson became a recruiting center for African-American troops.
Read more about the history here.