The reason? Ground zero today is too busy as an active construction site, CBS News Correspondent Jeff Glor reports.
Until this year, much of the progress rebuilding the World Trade Center site was invisible to passers-by because it was happening underground. Not anymore.
"We're extremely happy with the progress," said Chris Ward, executive director of the Port Authority of New York and New Jersey, the agency that owns the land and oversees rebuilding. "Eighty percent of the steel for the memorial plaza has been placed."
The memorial plaza, at street level, is largely built and decorated with its first grove of trees. The tallest building to fill the hole in the skyline has risen 375 feet. The 16-acre site hums to the dance of 16 cranes almost every day.
"We've probably knocked off 40 to 50 percent of this project just within the past year," Ward said.
Every week, another floor of the new 1 World Trade Center goes up, a building that's also been called the "freedom tower."
"Were there times you wondered if you would ever see this?" Glor asked.
"There are times I wonder this every day," Ward said.
The tower has 35 floors so far on its way to 105. By the end of this year, it should be halfway to the iconic 1,776 feet.
New York City school teacher Eileen Lugano has a deeply personal stake in the rebuilding. Her father was a steamfitter on the first trade center. Her son Sean Lugano, a stock broker, later worked in the south tower until 9/11.
Sean Lugano was just 28 years old, and he did not make it out. The tours Eileen Lugano leads once a week for the "tribute center" help her keep her son's memory alive.
"They're important because I am telling a story that must be remembered," Lugano said.
Remembering the 2,752 victims of the trade center attack will be the centerpiece of the site.
The granite for reflecting pools marking the footprints of the twin towers is done, said Lou Mendez, vice president of design and construction for the National September 11 Memorial and Museum. Starting next year, waterfalls will cascade 30 feet into those pools.
"They really create this large marker of absence, a sense of something that has been removed and cannot be replaced," Michael Arad, a designer for the memorial.
The names of the victims will be etched around the edge of the pools in bronze. This week, a pair of 70 foot, "forked" steel columns, salvaged from the ruins, were placed on the site. They're so large, the museum will be built around them.
For Eileen Lugano, honoring her son is her way of rebuilding for her, her four other children and her seven grandchildren, all born after 9/11.
"Life does go on, you know," said Lugano. "Joy returns. We celebrate everything he was and everything he is to us today."
The foundation in Sean Lugano's name has donated a practice field to Loyola College in Maryland, where he played rugby, and an annual scholarship for a senior attending Xavier High School, his alma mater, in Manhattan.