As a Houstonian, I am surprised it took me this long to explore the tunnel system. I was concerned I may feel a little claustrophobic or like the weight of the city was on my head, but I couldn't have felt more at ease. 20' below the service lies a little city untouched by sunlight. Built in the 1930's and finished in the 1950's-1960's, the tunnels go all over and are marked well with maps every so often. As with any structure and/or space, many of the sections have been renovated. Some spots have skylights from a neighboring building to allow a piece of daylight to be seen. There are restaurants, salons, A chiropractor, a dentist, dry cleaners, CVS, entrance to lofts, convenient stores, a recreation lounge with game table and much more!
There are tours you can take with a guide, but we decided to go on our own. Many of the bank building and office building have entrances into a portion of the tunnels; just depends where you drop in to where you will be in the system.
I noticed that many popular restaurants have a couple locations in the tunnel system. Chick-fil-A and Otto's to name a couple. Both establishments had more than one location. I assume this is for ease to the workers during their lunch break.
There is lots of information online about the tunnels development, issues during Houston flooding, etc. read more