It is a seven-mile-long maze of narrow corridors designed to replace street-level activity. Since Houston can get very hot in the summer, it was designed to house all restaurants and retail in an air-conditioned environment that would connect to all buildings in the business center. The tunnels are musty and confusing and offer no visual stimulation except for the store windows. The tunnels also detract from street-level activity, which desperately needs retail and amenities. Lastly, the tunnels offer no public seating. Either you sit to eat in the restaurants or keep walking.

With the exception of one entrance, the tunnels are only accessible if you enter through an office building. One could live in downtown for years and not know the tunnels exist. They are privately monitored and policed, and are only open during normal business hours.

The tunnels feel safe only when they are filled with people. Lighting and signage are inadequate, making navigation quite confusing. Also, the walls of the tunnels are blank and sterile.

The tunnels are congested part of the day because they are so narrow. They also lack identifiable gathering points and seating, making them merely a place to pass through.

This place is hidden for a reason. It is unattractive and uninviting. It is not a place where people meet. There is very little to see, so it is not an attraction, and its drabby feel does not entice people to stay or linger.

The first few tunnels were constructed in the early 1930's, but soon fell into disuse. In the 1960's private developers began to construct new ones, equipping them with air conditioning and renting space to various businesses. Today, almost every major building in downtown Houston is connected to the system, though only one of the dozens of entrances connects them to the street. The system is almost entirely privately owned in small segments by the buildings standing over them. This haphazard and unplanned construction explains why they are so confusing to newcomers and visitors.