Final answer:
During Prohibition, bootleggers produced alcohol in hidden cellars and basements, underground distilleries, and secret breweries and warehouses.
Step-by-step explanation:
The production of alcohol during Prohibition was carried out in various clandestine locations. Bootleggers produced alcohol in hidden cellars and basements, where they could hide their operations from authorities. They also set up underground distilleries to produce alcohol secretly. Additionally, some bootleggers established secret breweries and warehouses to manufacture and store alcohol illegally.