A Sept. 11 memorial is taking shape at ground zero, with a nearly completed reflecting pool the size of the World Trade Center's north tower footprint.
New aerial photos show the pool, one of two being built over the twin towers' footprints. The pool is the first piece of the Manhattan site that looks like many of the years-old renderings of plans for office towers and other facilities.
The pools are designed to reflect the voids left when the towers collapsed in 2001. The steel structure that's been built is at street level and shows where water will cascade from the sides and into a void in the center.
The Port Authority of New York and New Jersey owns the site and recently installed 1,600 tons of steel at the memorial.
The memorial and an underground museum are expected to be completed by 2012.