Flight 93 National Memorial
The ride started on Friday in Shanksville, Penn. at the Flight 93 National Memorial. Riders then made their way to the Pentagon before heading to Manhattan.
President Barack Obama, along with first lady Michelle Obama, Vice President Joe Biden and wife Jill Biden, walked out of the White House at 8:46 a.m., the moment the first plane hit the World Trade Center.
Families of those who died aboard United Airlines Flight 93 asked lawmakers and Obama administration officials on Wednesday to set aside federal money to complete a 9/11 memorial at the crash site in Pennsylvania.