The Alamo defenders are often shown to stand shoulder to shoulder. In effect, the perimeter of the Alamo was almost 450 yards. One hundred and eighty men needed to be some seven feet apart to confront an attack from all sides.
A glaring problem with this film's casting is the fact that almost all the major players in the Alamo siege are portrayed by actors who are ridiculously overage for their parts. Jim Bowie, for instance, was only 39 at the time of the siege, while James Arness was 64 at the time of filming. Davy Crockett was 49, while Brian Keith was 65, and Lorne Greene was a 72-year-old playing a Sam Houston who was 43 in 1836. Alec Baldwin is reasonably close at 29 to William Travis's actual age of 26 and Raul Julia was 47 at the time while Santa Anna was 42.