The Alamo gates were filmed very quickly, one or two takes at most. However, the march through San Antonio was organized and roads were blocked off two blocks away once filming began. The actual scene that stopped filming was when a single shot rang out in the Alamo during the ending sequence of the movie. This angered some locals, who claimed that the site is a shrine and that no gunfire had been fired there since the original battle.
All unfinished scenes were completed when the company relocated to Rome, Italy. Most of the key scenes needed, that could not be completed in Rome, were those showing the backdrop of the Alamo, filmed by second unit crews in the street. The scenes in front of the Alamo were shot early Sunday mornings, unbeknownst to local authorities. Several locals walking the streets early that morning were startled by police cars, National Guardsmen, and soldiers rushing the Alamo across the Cenotaph Memorial.
Refers to the John Wayne film The Alamo (1960) by showing a painting of Wayne as Davy Crockett defending the Alamo. Normally there is a disclaimer that states "all characters depicted in this motion picture are fictitious," et cetera. In this movie, the disclaimer reads "all characters depicted in this motion picture except John Wayne are fictitious..."
Due to protests from locals when they found out about the plot, the Mexican Army recapturing the Alamo, production was halted, although some major scenes had already been shot inside the Alamo. These keys scenes were The Tour, The Climbing of the Barrack Wall, and the Sacristy. The company was only allowed to film scenes up to the front gate after production was halted. The scene where John Astin replaced the flag was filmed on a Hollywood business street. The scene in CBS Television's city backlot was also used in The Omega Man (1971).