One World Trade Center spire harbinger of construction completion

(CBS News) A symbolically important piece of the new One World Trade Center is taking its position Wednesday in New York City. It's the building's giant spire for the top of the tower.

Nine of the 18 massive steel pieces that will eventually make up the 408-foot spire -- some weighing nearly 70 tons -- were too heavy to be driven in from Canada where they were constructed. So instead, they made the 1,500 nautical-mile trek along the Atlantic Seaboard into Lower Manhattan.

Spire for One World Trade Center arrives in NYC

The heavy lifting went well into the night with crews using a large crane to move each piece from the barge onto a flatbed truck.

Earlier Tuesday, workers poured cement atop the 104-story skyscraper where the spire will be locked into place.

Steven Plate -- the man heading up the construction project -- calls the whole task a tremendous technical challenge. "This project truly has really redefined construction I think throughout the world on all levels whether it be construction, whether it be design, whether it be logistics," he said. "Keeping in mind, we're building a city within a city."

The building sits atop sacred ground for Americans -- the site of the worst terrorist attack in U.S. history.

Now, after years of delays, from the depths of devastation, the new 16-acre site is well on its way to completion. The tower at One World Trade Center became the tallest building in New York back in April.

It could take three months for the final piece of the spire to be put into place. But when it's done, the tower will be the tallest building in the Western Hemisphere, reaching a symbolic 1,776 feet.

Watch Terrell Brown's full report above.