On September 11, 2001, terrorist hijackers steered two jets into the World Trade Center's Twin Towers, setting them ablaze and causing their collapse, killing 2,753 people and injuring countless others. The 16 acres of fenced-in rubble and debris that slowly evolved into a construction zone known as “Ground Zero” quickly became a memorial unto itself, a place where visitors and those who lost loved ones could mourn and reflect on what was the single-most-deadly foreign attack ever to happen on American soil. Exactly a decade later, the 9/11 Memorial Plaza opened, giving thousands of annual visitors a solemn, dedicated place to commemorate the events of that infamous day. After many delays, the accompanying underground National 9/11 Museum opened in 2014, on the same bedrock once used to support the Twin Towers’ foundation. It serves as a fitting, if somber home to a vast array of artifacts from 9/11 and its aftermath. The Memorial Plaza’s twin reflecting pools are bordered by four
distinct skyscrapers: the 1,776-foot One World Trade Center, and Towers 2, 3, and 4, each designed by renowned architects and rising 80-plus, 80, and 72 stories, respectively. The site also includes the WTC Transportation Hub designed by Santiago Calatrava. Known for a time as the “Freedom Tower,” the 104-story One WTC has a roof that’s 1,368 feet tall—a height identical to the original 1 WTC, the “north tower.” (The south tower, or original 2 WTC, stood 1,362 feet tall.) An illuminated antenna further increases the new skyscraper’s height to 1,776 feet to commemorate America’s founding, and earning its title as the tallest building in the Western Hemisphere. Designed by award-winning architect David Childs, the new One WTC opened to tenants in late 2014. One World Observatory, on its 100th, 101st, and 102nd floors, opened in May 2015. With its angular, mirrored-glass facade, the Fumihiko Maki–designed 4 WTC anchors the southeastern corner of the complex, and was the first tower to open on the site, in late 2013. On its north side, 3 WTC is under construction and slated to open in 2018. At the site’s northeast corner, 2 WTC construction restarted after several major delays, and is now expected to open in 2020. Between Towers 2 and 3 stands the eye-catching, $3.9 billion WTC Transportation Hub, which serves as the terminal for New Jersey’s PATH trains and an underground link to Brookfield Place, as well as 10 subway lines and the Fulton Center transit complex. Inspired by the image of a bird in flight, the iconic hub features massive white steel “wings” extending from its riblike substructure. A largely column-free interior and glass-paneled roof allows natural light into the terminal’s lower floors. The multilevel hub connects underground to Towers 2, 3 and 4, and offers more than 360,000 square feet of shops and restaurants. As you plan your visit, set aside time to check out other key parts of the 9/11 story, such as St. Paul's Chapel, the Tribute Center, and the “Ten House” firehouse on Liberty Street.