Underground tunnel

so there is a location of an underground tunnel that I might explore soon, there is supposedly an abandoned tank and some other stuff down there. The tunnels had various uses, one of being used by bootleggers during prohibition, also there are rumors and legends of the tunnels going under the old jailhouse and going under some of the big cathedral churches. some oldtimers say their was an entire city down there.this might be a bust but if we can find the entry way down I think this would be a very cool place to explore.