Today, citys' secrets. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

You know Guy Noir's tagline, "A dark night in a city that knows how to keep its secrets." Well, what city doesn't have its secrets? Some years ago I did a program on Stanley Greenberg's book, Invisible New York, about the secret recesses of that city.

Houston, Texas, is somewhat smaller and a lot younger, but none of us lives here very long without making all kinds of secret places uniquely ours. Many of mine are on the University of Houston campus: our Meditation Garden, the mysterious statue in the middle of our University Center. (It harbors symbolism that only we old-timers know.) The forested banks of the Bayou running through the campus, so rich in water birds. Of course, any other part of the city harbors secrets of its own. 

And few of us ever think about the greatest secret of any city: its subterranean mirror image. For just below the surface lie telephone conduits and electric power ducts. Further down are gas lines, low-pressure domestic water, high-pressure water for fire-fighting. Deeper yet we find sewage lines, storm drains, and building foundations. 

Systems of tunnels often serve the utilities. In many large cities, below all else run subway tunnels, linked to the surface only by long ventilation shafts. The shining city above ground is inevitably served by that second invisible city below -- the one we hardly know is there. 

Of course, as cities grow, the trenchers and powered shovels come in to expose its subterranean past. So much urban archeology is what's called reclamation archaeology. Every time a new building goes up, a new past is exposed below. Take the building of New York's BMT subway line in 1912. At one point, excavators burst into a huge closed room decked out in Victorian splendor. A small pneumatic subway, built there 46 years before, had failed as a business venture, been sealed up, and forgotten. 

We have a splendid secret subterranean place here in Houston -- our system of downtown underground tunnels. Seven miles of tunnels link some 95 city blocks and hold every kind of shop and service. How can such a thing be secret? Well, how many of you, my Houston listeners, have actually walked and used that system? It really does remain a secret to more people than not.

So, your assignment today is: Go out and find the unexpected. Here in Houston that might be the old Gable Street Power Station or the 1940 Air Terminal Museum. Both are architectural relics, too little known and too seldom visited. Or maybe you'll simply find your own family of barn swallows below a bayou bridge. 

Our secret place might be no more than a special shop or restaurant. No matter, a city becomes ours when we feel we own its special places. When you or I own our city, we become its custodian. And that's the point at which all those secret places truly serve the common good.

I'm John Lienhard at the University of Houston, where we're interested in the way inventive minds work.

See the Discover Houston Tours site for more on special places in Houston. All photos by J. Lienhard

Note Added, March 19, 2015: Since this episode was first run in early 2010, one of these Secret Places is no more. Ron Bass has written to point out that the Gable Street Power Station was razed in 2011. It was not the first nor will it be the last such landmark to be lost. I recall my horror when the great silos of the Old Rice Mill on Studewood went down in 1996. 

A few more special places -- "secret" only to those who have not seen them.:
 

Fountain in the shadow of the Transco/Williams Tower 


Whistling ducks in the Meditation Garden pool by the UH engineering and architecture buildings. 


Small park and lighthouse near the Southshore Marina in Houston 


Viewing plaza overlooking Buffalo Bayou below the Houston Grand Opera House