The floors are also designed to bear an extremely large amount of weight.

The building continued to function as AT&Ts long distance telephone exchange until 1999.

After that AT&T vacated the building and moved to another a few blocks away.

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There is another one at Houston, for instance.

AT&T Building at Houston.

One wall is completely devoid of windows.

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Photo credit:Wolfgang Houston/Panoramio

AT&T Building at Houston.

Photo credit:Bobby Burning7Chrome Quine/Panoramio

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