The Port Authority of New York and New Jersey and The Durst Organization will test the beacon and spire on One World Trade Center at 5:30 p.m. today.

The test comes six months after iron workers completed its installation, which puts the new New York icon at 1,776 feet.

The 408-foot structure is assembled with 288 50-watt LED modules, which will enable it to be visible up to 50 miles away. It will also provide transmission services for the region's broadcast outlets.