On Friday, we went down to the World Trade Center site to see how construction of 1 World Trade Center and the 9/11 Memorial is progressing. It's striking how much progress there has been since April last year, when we last visited: The plaza and 9/11 museum pavilion seem nearly complete, and 1 WTC is officially a skyscraper, rising more than 70 stories above Ground Zero and visible for miles around.

We asked Chris Ward, the Executive Director of the Port Authority, how so much had gotten done this year. Through a spokesman, he told us "We are building a city within a city. Three years ago, we decided where this project should be on the 10th Anniversary and every year after. Establish clear goals and priorities, then harness the imagination and ingenuity of our builders - that has been the path to progress." Those builders now include more than 3,000 construction workers— the most who have ever been working at the site.

Click away for a full tour of the site, including 1 WTC, the memorial pools and plaza, and a preview of the 9/11 Museum.