This year’s Pearl Harbor remembrance marks a historic first: none of the 12 surviving centenarians are able to attend the ceremony in Hawaii, ending the era of firsthand witnesses at the event.

The attack in 1941 killed over 2,300 troops and drew the U.S. into World War II, and while survivors have long been central to commemorations, their numbers have dwindled from thousands to just a few dozen in recent decades.

Efforts to preserve their stories have expanded, including nearly 800 oral histories recorded by the National Park Service and over 500 collections held by the Library of Congress.

Organizations like the Sons and Daughters of Pearl Harbor Survivors continue to share family stories in schools, parades, and public presentations, CNN has reported.

As eyewitnesses disappear, descendants and historical projects are increasingly responsible for keeping the memory and lessons of Pearl Harbor alive.