It's not exactly the bands but there are plenty of men and women harder work any -- special. Underground city. Whatever you do though don't call these tapes and we don't -- decades. -- where the trouble is the world's largest. Yes the world's largest underground business complex with the world's largest screen are. Oral Roberts is in charge of the complex known as does -- Place. It's a series of underground tunnels that are home to several businesses. This massive complex is 55. Million square feet. And runs all the way from 210 highway -- the property line for world defined. It all started when a mining company began removing limestone. Back in the 1940s. In the mid sixties everybody thought about what with the after Houston was there an after use. He had done by the late sixties we had an underground storage company. And what I always like to stay is we still have tenants here that have grown with us 68 to ten since the late seventy. The complex contains seven miles of lighted and paved roads and several miles of railroad tracks. One huge advantage is in fact the -- travelers has a constant year round temperature of 65 to seventy degrees. That makes it ideal for all types of businesses. Including the EPA. Post office and auto companies. Robbie Harris is the general manager of now tied. Currently. We are using. The caves or are updating. 150s. Soon to be. Updating -- nutrients that this could be produced in the Kansas and -- -- cycle plant. Now some disadvantages of working in this underground city is the fact you have limited if any cellphone service. And the fact there are no windows so you have no idea what's really going on outside. And so we end up with our office it's so like the cooler here pillar is. You know. The better here opposites coming up in part to -- ties to some -- this has the chiefs and what lies ahead for this massive complex. Mike -- -- ABC news.