For a few years in the late 1970's Massachusetts lowered the drinking age to 18, which made it legal for Academy students to drink alcohol. The school responded to this by opening the Pub in cooperation with the Inn. Located in the basement of the Inn, it had games and food as well, much like The Den, but without alcohol. With the return of the drinking age to 21, the Pub disappeared from campus life.
"Andover Pub," in NOBLE Digital Heritage, Item #15767, http://heritage.noblenet.org/items/show/15767 (accessed May 5, 2016).