Despite the detrimental effects of alcohol on adolescent health, high rates of alcohol use are reported among Tanzanian youth. We conducted systematic community mapping and participatory group activities with 177 adolescents in Dar es Salaam to explore how alcohol outlet density and advertising may contribute to adolescent drinking in urban Tanzania. Findings revealed a high density of alcohol-selling outlets and outdoor advertisements. The abundance of alcohol-related cues, including their close proximity to places where youth congregate, may facilitate and increase adolescent alcohol use in Tanzania. Participants recommended several changes to the alcohol environment to reduce adolescent drinking. Structural interventions that reduce adolescents' access and exposure to alcohol are needed in Tanzania.