The new San Francisco 49ers Stadium in Santa Clara is already a towering steel skeleton that rises nearly 200 feet high above a large lot near the intersection of Centennial Boulevard and Tasman Drive.

Although the ground inside the rising stadium is dusty, it is also solid -- reinforced by 3,000 foundation piles to create a firm support for the four gargantuan cranes that can stretch to a towering 338 feet inside the steel oval.

At center of it all is what Stadium Project Executive Jack Hill refers to as hallowed ground: the 50-yard line, which also marks the "geo center" of the construction site.

"We treat it as sacred," Hill said.

According to the 49ers, the $1.2 billion, 68,500-seat stadium is already 15 percent done and on schedule to be completed and open for the 2014
NFL season.

Since Santa Clara city leaders joined 49ers players, fans and team officials for the stadium's groundbreaking event in April, construction has
progressed at an aggressive pace.

More than 50 miles of pipe has already been laid and 17,000 cubic yards of concrete poured. In the end, the stadium is expected to use about 14,000 pieces of steel, weighing an estimated 18,000 tons.

At first, construction on the site was going 24-hours-a-day. Now, it has slowed to the still ambitious clip of double shifts, six days per-week, Hill said.

Masons, electricians, plumbers and a plethora of ironworkers are working on site from 6 a.m. until midnight, Hill said.

"We're at a good, aggressive, comfortable pace," Hill said, adding, "We think we're at the right pace to finish the job in 2014... We're not working 7 days-a-week, but it kind of feels like it."

At the end of next month, Hill said, workers will start to fill in some of the pre-cast concrete to make a base for the seats, then the lights,
then some more of the inner components.

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