 The initial phase of permanent construction of the Flight 93 National Memorial, including the visitor's center, was completed by the 10th anniversary in 2011.The memorial is built around the crash site, following the plane's flight path, and protecting the area of impact, known as the "Sacred Ground", which remains protected and accessible only to family members of the passengers and crew.Shanksville's volunteer firefighters, as well as emergency personnel from nearby towns of Central City, Somerset, and others, had rushed to the United Airlines Flight 93 crash scene to search for survivors.