Observances are being held all over the United States to mark the 10th anniversary of the day when terrorists hijacked airliners and flew them into the World Trade Center and the Pentagon. Here is a sampling of the coverage.

World Trade Center Memorial Set to Open

Crowds are streaming to New York City for the opening of a memorial set up on "hallowed ground" -- pools with cascading waterfalls built in the place of the two missing World Trade Center towers. For more details on the ceremonies, see ABC News.

Some New Yorkers Trying Not to Dwell on Anniversary

Laurel Wells is not going to the official Sept. 11 ceremony on Sunday morning in New York City. And she's not alone. Details on The New York Times.

A U.S. Capital Forever Altered

Since the 9/11 terrorist attacks, Washington has seen both subtle and significant changes to its landscape. See photos and descriptions on The Washington Post.

Doctor Preserves Oral History of Ground Zero Responders

First responders relive their haunting experiences on their road to recovery and the doctor who is preserving their oral histories. See 60 Minutes on CBS News.

Heroes of Flight 93 Honored in PA

Bells tolled 40 times in Shanksville, PA, in a ceremony in which the names were read of the 40 passengers and crew who died after terrorists hijacked UAL 93. As the world knows, with passengers in rebellion, the plane slammed into a field, killing all aboard. Get the details, on The New York Times.