For the fortress, please see Alamo.
The Alamo was a movie produced on Earth in 1960 that depicted the Battle of the Alamo. It starred actors John Wayne as Davy Crockett, Laurence Harvey as William B. Travis and Richard Widmark.
The reference to Widmark was an indirect reference made to Jim Bowie.
Vic Fontaine was familiar with this movie, stating that it had great battle scenes, nice sets, but that it was way too long. (DS9: "Badda-Bing, Badda-Bang")