The tunnels are definitely interesting. It gets you place to place underground in downtown Houston. There's a few shops and restaruants to visit, but nothing extraordinary.

If you have time, and nothing else to do, give it a visit. Otherwise, it's just there.

The downtown tunnel system is an excellent system for downtown workers who need to get to the various downtown buildings. There are restaurants and shops down under, but not anything worth going back for. It's strictly an experience. If you've done it once, most likely you won't want to do it again, unless you are a downtown worker.

Might as well walk in the mall. And I always get lost anyway....