One World Trade Center is the tallest building in the World Trade Center complex in New York City (which was rebuilt after the original Twin Towers were destroyed in the terrorist attacks of September 11, 2001). It is currently the tallest building in North America and the Western Hemisphere. The building occupies a square footprint that is the same size as each original tower and has a 185-foot tall concrete base that is resistant to ground-level attacks. It then tapers at the corners of the square to form an octagon at the middle of the building and then a smaller square at the very top (that is oriented 45 degrees from the base). Given the history that led to its construction, One World Trade Center is widely seen as a symbol of resilience and hope.