After more than a decade, following their cancellation after 9/11, and the half-decade it took for the Space & Rocket Center to get transportation lined up, tours of the Marshall Space Flight Center resume today.
The USSRC has a web page up regarding the tours. No times are listed, you have to call for those (naturally). Tours will run once per day from Sunday to Thursday. On Fridays and Saturdays there will be two tours per day.