Papadopoulos, who was already an owner of a popular Boston-based folk club called the Unicorn, hastily put together the Psychedelic Supermarket in an abandoned parking garage to cash in on the scheduled performances dropped by the Crosstown Bus after it was shut down by police.
[2] On September 8, 1967, the Supermarket opened to an eight-day stay by Cream, just as the psychedelic rock group was preparing to record their second album Disraeli Gears.
The venue was described as a "very industrial place" that had walls littered with album covers, no windows, and could hold between 200 and 300 patrons, but in its beginning stages the Supermarket had no seats installed.
Throughout its existence, the venue featured a mixture of nationally recognized acts such as the Grateful Dead, Moby Grape, and Country Joe and the Fish, and local Boston bands like Eden's Children, the Freeborne, and Listening.
[1] In 1969, Papadopoulos closed the original site of the Unicorn Coffee House (733-825 Boylston Street, Back Bay, Boston) and moved its operations into the Psychedelic Supermarket.