A warship built with steel salvaged from the wreckage of the World Trade Centre set sail for New York on Tuesday.
Hundreds of people lined the banks of the Mississippi river near New Orleans as the USS New York sailed through the fog, local media reports.
Its bow stem contains 7.5 tons of steel salvaged from the rubble following the terrorist attacks of September 11, 2001.
"That steel means a whole lot more than just metal," Ronnie Harris, mayor of nearby Gretna, Louisiana told the local Fox News station amid a swell of patriot music.
"The entire country comes together in the form of that bow stem and I'm so proud that this event puts it in the history books and in people's minds."
The 208-metre long ship's main mission is to transport and deploy combat and support elements of Marine expeditionary units, the US Navy said.
It will carry approximately 720 troops and can deploy helicopters and other aircraft from its massive deck.
Two other ships - the Arlington and Somerset - are being built in honour of the victims of the attacks on the Pentagon and United Flight 93 and are also incorporating materials salvaged from those sites.