Located in downtown Los Angeles and commonly known as the First Interstate Building, it has offically reverted to its orginal name, the Library Tower, when First Interstate Bank was bought out by Wells Fargo Bank (Other than the news, I haven't heard anyone call it by that yet).
It was built by an urban development team for one reason, to save the arson fire damaged Los Angeles Central Library, thus its orginal name. It was completed in 1990 where as shortly after the First Interstate Bancorp made a deal for it to be renamed after First Interstate to occupy a portion of the building.
It is the tallest building ever constructed in a major earthquake zone (The San Andreas Fault is located just 26 miles from it), and is famous for being the "tallest building west of the Mississippi," which it is. It also is the 8th largest in the United States.