That's awesome. I grew up in kc mo and my grandparents had many stories about the river market area during prohibition time. Gramps would often recall stories of stills hidden behind walls in basement and tunnels connecting secret places.
I bet you heard some great and very true stories from your Grandparents Obsessive! Your Grandparents might of known mine! lol!
Your Gramps is right about the hidden rooms with stills, storage, distribution sites, speakeasies and tunnels connecting these places in Kansas City. The River Quay (River Market) was the hub of these activities in the area... working closely with river towns up and down the Missouri as well as the smaller towns around...one distribution site I've been to handled Nebraska exclusively.
I've been in tunnels in homes that led to underground party rooms (and hidden exits and another tunnel) that were decorated as nice as an upscale bar would be today. The tunnels and hidden rooms in legitimate businesses were the same... a little more added danger in some for being exposed depending on who owned them...Had to throw some of the law a bone at times...for publicity purposes. For the most part, where I've been, the Speakeasies hidden behind walls in nice restaurants were just like what was out front. It's really interesting to see.
During the times before and after the Volstead Act... Moonshining was going on and continued for a lot of folks to avoid liquor taxes. It was also a way of life for some immigrant ethnic groups. I usually hunt sites up to the mid 1940's-1951...not that it stopped then, but in these areas a lot of times homes and buildings stayed in the family. Now, a few of the areas have been taken over by immigrants that I have no ties to, wouldn't blend in and they would never let a stranger on the property...truthfully in some of these areas, I wouldn't go..even with 4-5 armed companions..lol!
I'm going to post some photos, taken from a VCR tape that I recorded of a site that I was at a long time ago...I knew it had been discovered long after I was there and was going to be on the news, so I recorded it. I normally wouldn't think about posting photos of these types of sites but since it was made public and on the news after the contractors discovered it and contacted them I'm not compromising anyone's home or identity.
The original owners (on paper) had died and a new owner was having some contractors do some work in the basement and they found one entrance to the hidden room while doing the work. There were two other entrances/exits but at that time they hadn't found them. I don't know about now. I haven't been back there..I hunted it then... although I didn't have a small coil at the time

but I did get a few souvenirs. I'd love to go back now with this set up.
The photos will give an idea of what I was describing in my other more recent thread where I found the pop out Barber Half with my newly acquired AT Max with the 5x8 coil. These basements and/or cellar hidden rooms are pretty much the same type of rock foundations and rock and dirt flooring... Except the Speakeasies are much nicer and more brick,plaster and wood.
The photos, I'll post on the other thread 'She Was Eyeballing Me' if you haven't seen that one.
I'd love to hear the stories your Grandparents told you!
Thank You!
Kace