[4] As the largest bas-relief military monument in the United States, it honors the Mormon Battalion, the U.S. 1st Dragoons, and the New York Volunteers who raised the American flag over the fort on July 4, 1847, at the first Independence Day in Los Angeles.

Featuring four different panels, a 78 feet (24 m) by 45 feet (14 m) terra cotta panel designed by Saltus Award-winner Henry Kreis is the most prominent feature and portrays the July 4 event.

Other panels represent the agricultural and spiritual foundation of the region; transportation that shaped the city at the end of the 19th century; and the crucial role that water and electricity play in a large modern city.

It was out of service since a 1977 drought, and turned on in December 2018 after restoration work was completed.

The pylon features a 16 feet (4.9 m) by 11 feet (3.4 m) American eagle as well as an incised relief on the low wall along the sidewalk depicting the 1,100-mile (1,770 km) march of the Mormon Battalion from Council Bluffs, Iowa, to Los Angeles.