The terra cotta art wall designed by Henry Kreis is the most notable feature of the memorial. Fabricated by the prominent California terra cotta manufacturer Gladding, McBean, it was reported at the time of its installation to be the largest bas-relief in the United States. This is the only public artwork in Los Angeles portraying an historic event that occurred at the actual site of the work. It depicts the ceremonial flag being raised over the fort on July 4, 1847. To ensure the authenticity of the uniforms worn by the U.S. First Dragoons, the New York Volunteers and the Mormon Batallion - the units witnessing the ceremony - Kreis was advised by noted California historians Glenn Dumke and Robert Cleland. Historic themes in the development of Los Angeles are symbolized in the other three reliefs: the uppermost represents the agricultural and spiritual foundation of the region; the middle panel depicts the transportation that shaped the city at the end of the 19th century; and the lower section contains an inscription written by the Department of Water & Power and portrays the crucial role that water, and electricity play in a large modern city. On January 12, 1847, two days after United States troops occupied Los Angeles during the war with Mexico, construction of an adobe fort began on top of the hill where the Fort Moore Pioneer Memorial is now located. Completed by the Mormon Battalion, which arrived in Los Angeles in March, the fort was dedicated on July 4, 1847, and remained in service only until 1853, when it was decommissioned. It was named in memory of Captain Benjamin Davies Moore who was one of 21 Americans killed during the battle of San Pasqual near San Diego in December 1846. Though this battle, the largest in California during the Mexican-American War, was a military victory for the Californians led by Andres Pico, it failed to stop American forces from capturing Los Angeles a month later. To the right of the bas relief is an 80-foot-long waterfall that has been out of service since the 1977 drought. A 237-foot-long brick facade, serving as a backdrop for a 68-foot-high pylon, is the largest part of the Memorial. Albert Stewart designed the 16' x 11' American eagle on the pylon as well as the incised relief on the low wall along the sidewalk depicting in narrative form the 1100-mile march of the Mormon Battalion from Council Bluffs, Iowa to Los Angeles. A full restoration of the memorial began in 2016.

A Connecticut-based, German-born sculptor, Henry Kreis, designed the most notable feature of the monument: the large terra-cotta mural panel. Kreis’s highly stylized design depicts American troops raising the flag, and a series of flanking vignettes show regional scenes such as orange groves, cattle ranching, and water and power systems, to name a few. Kreis’s panels were fabricated by the legendary Gladding, McBean who produced innumerable architectural terra-cotta pieces since the 1930s. Albert Stewart (1900–1965) was born in London and emigrated to the U.S. as a child with his family. He studied at the Beaux Arts Institute and the Art Student’s League in New York City, and served as an assistant to sculptors Frederick MacMonnies and Paul Manship before he began sculpting in the 1930s. Stewart taught sculpture at Scripps College in Claremont for 25 years. Notable works include figures on the Scottish Rites Temple on Wilshire Boulevard and on the exterior of the Life Science Building at UCLA.