NEW YORK -- A 600-ton crane has delivered six granite monoliths to the World Trade Center -- stone sculptures honouring those who were sickened or died from toxins while cleaning up the site of the terrorist attack.

On Saturday, the chiseled granite pieces were in place, pointing skyward to also honour rescue, recovery and relief workers facing the 9-11 aftermath.

The monoliths were chiseled from the Rock of Ages granite manufacturing company in Barre, Vermont, using Canadian granite.

Steel salvaged from the original World Trade Center was incorporated into the stone structures outside the National September 11 Memorial & Museum.

Visitors can use a pathway flanked by the monoliths that symbolize New York's strength and determination through adversity.

Costs were covered by New York state, plus fundraising and private donations.