College football in Alabama is not merely a sport — it is the dominant organizing obsession of public life, dividing the state between Alabama Crimson Tide and Auburn Tigers fans with a seriousness that confounds outsiders. Birmingham hosts the Iron Bowl, the annual Alabama-Auburn game, at Legion Field or at the competing home stadiums (Tuscaloosa for Alabama, Auburn for Auburn), and the city shuts down accordingly.
If you are visiting Birmingham during football season (September through December), your experience will be shaped by whether there's a game that weekend. Hotels book out months in advance for Iron Bowl weekends. If you have no particular interest in college football, be aware of the schedule. If you do, few sporting events in the country offer this level of intensity.