storey: one level in a building
cutting-edge: modern
exclusive: for the use of one person or group
ventilation: the circulation of air
One World Trade Center Stands 1,776 Feet High
With the observation deck and antenna, the 104-storey One World Trade Center (One WTC) stands 1,776 feet tall. This number represents the year the Declaration of Independence was signed (July 4, 1776). The skyscraper, previously known as The Freedom Tower, was built with several cutting-edge safety features, including a set of stairwells exclusively for emergency workers and a ventilation system with biochemical filters. One WTC is also one of the most environmentally-friendly office buildings in the world. Approximately 75% of the building materials were recycled from construction sites and up to 70% of its power comes from green energy. One WTC stands high above the two large reflecting pools where the Twin Towers previously stood.
