Obama was touring the 22nd floor of One World Trade Center in lower Manhattan, walking along the unfinished cement floor and stopping at easels set up with renderings of what the completed tower will look like.
The president was joined by first lady Michelle Obama, New York Gov. Andrew Cuomo, New York City Mayor Michael Bloomberg and other officials.
The Obamas were meeting with workers and signing the final steel beams that will be installed as part of the building's framework.
The skyscraper is expected to be completed in early 2014.
