This was an expansion project with significant technical challenges, from the new construction convention space built over a continuously open six-lane freeway (Interstate 670 runs underneath the convention center), to the installation of four, 300-foot (90 m) pylons to support the facility's roof. The result - the largest, column-free convention environment in the world. An aluminum installation, 'SkyStation', by artist R.M. Fisher tops each of the four pylons that support the building. The four tall art deco pylons are a highly noticeable fixture in the Kansas City skyline.