Downtown Phoenix Arizona Tunnel system.

I've lived here all my life and never knew there was a tunnel system downtown.

In those days they didn’t have air conditioning so the tunnels were created with fans to pull air in to cool down the hotels. But they weren’t only used for this reason for long.

Phoenix were very good at keeping secrets. Gambling was outlawed in 1907 and in the 1920s prohibition was introduced so saloons and speakeasies would make their way through the tunnels. A speakeasy was an establishment that would sell alcohol illegally. Some of the prominent hotels would have access to these speakeasies through the tunnel system.

https://journeyscope.com/phoenix-arizona/