During the perio of Prohibition in the United States, Montreal became well known as one of North America's "sin cities" with unparalleled nightlife, a reputation it still holds today. In part, its bustling nightlife is attributed to its relatively late "last call" (3 a.m.), a large university population, the drinking age of 18, and the excellent public transportation system combines with other aspects of the Montreal culture to make the city's night life unique. The diversity of the clubs in Montreal attests to the popularity of its night life, with night clubs, pubs, bars and singing bars ("boîte à chanson"), latin clubs, african clubs, jazz clubs, lounges, after-hours houses, and strip clubs all attracting different types of customers.