NEW YORK (AP) — Americans are commemorating the 25th anniversary of 9/11, remembering the shock, the dead and the sweeping consequences of the al-Qaida attacks on symbols of U.S. might and prosperity.

Friday’s milestone anniversary will bring memorial rituals — wreath-laying, flag-flying, moments of silence, vigils and readings of victims’ names — and volunteer projects in tribute to a day that about half of U.S. adults remember as the most historic event of their lifetime, according to a new poll.