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.
Colonel Travis didn't die near the end of the battle with a shot to his hip. According to his slave Joe, whom witnessed it, Travis was struck in the head and killed at the very beginning of the battle.
Bowie was too ill to leave his bed, much less fight. He was shot and bayonetted where he lay.
The fall of the Alamo occurred before dawn on 6 March 1836 and was over around dawn. Compare this to the film that has it happening in broad daylight.
Although Travis ordered a uniform to be made, it was not ready by the time of the battle.
The Texian defenders sneak out of the fort and sabotage several Mexican cannons by clogging the cannons. However, it's blatantly obvious these cannons are plugged. Yet the Mexican soldiers try to fire the cannons. They wouldn't be able to load the cannons if they were plugged. If they tried to load, they would see the obstructions.
According to most accounts Travis was shot and killed at the onset of the final charge, but Alec Baldwin's Travis does not die until near the end.
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.