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Ann Arbor has a long history of openness to marijuana, given Ann Arbor's decriminalization of cannabis, the large number of medical marijuana dispensaries in the city (one dispensary, called People's Co-op, was directly across the street from Michigan Stadium until zoning forced it to move one mile to the west), the large number of pro-marijuana residents, and the annual Hash Bash: an event that is held on the first Saturday of April. Until (at least) the successful passage of Michigan's medical marijuana law, the event had arguably strayed from its initial intent, although for years, a number of attendees have received serious legal responses due to marijuana use on University of Michigan property, which does not fall under the City's progressive and compassionate ticketing program.

What annual event is held on the 1st saturday of april?
annual Hash Bash