NEW YORK (AP) — President Barack Obama will help open the National September 11 Memorial Museum today in New York.

He'll dedicate the museum along with 9/11 survivors, rescuers and victims' families.

The museum extends 70 feet underground to the twin towers' foundations, and it honors the nearly 3,000 people killed in New York, Washington and the Pennsylvania countryside by terrorists on September 11, 2001.

The museum opens to the public May 21.

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