Ground zero's Freedom Tower (search), redesigned to address security concerns, will lose the distinctive asymmetrical shape envisioned in earlier plans, but will be the strongest and safest building in the world when it is complete, officials said.

The redesigned tower will be straighter and squarer, but will rise from a base clad in shimmering metals chosen for both beauty and blast-resistance, and will be topped with an illuminated spire that will throw a beam of light to the horizon.

The details were part of a redesign detailed Wednesday for the soaring skyscraper, a project which has morphed from an emblem of New York's drive to rebuild lower Manhattan to a symbol of bureaucratic squabbling and delay.

The new design for the 1,776-foot tower is meant to make it more resistant to truck bombs. The building will now be 90 feet — instead of 25 feet — from West Street, a major north-south thoroughfare along the Hudson River.

Its main roof will be the same height as the fallen World Trade Center (search).

"In a subtle but important way, this building recalls ... those buildings that we lost," said its lead architect, David Childs.

The tower's cubic base will be clad in luminous materials — probably a mixture of stainless steel and titanium — that will be shimmering and light-reflective as well as blast-resistant, according to an online description of the redesign issued by the Lower Manhattan Development Corporation.

The strengthened structure, as proposed in the original design, will exceed city fire code requirements and include extra fireproofing, as well as biological and chemical filters in its air supply system.

Other safety features from the original design will include extra-wide emergency stairs, a dedicated staircase for firefighters, enhanced elevators housed in a protected core, and "areas of refuge" on each floor. Stairs, communications, risers, sprinklers and elevators will be encased in 3-foot-thick walls.

"The redesigned Freedom Tower speaks to the government and private sector's deep and abiding commitment to rebuild New York City to the highest architectural, environmental and safety standards," said World Trade Center site developer Larry Silverstein (search).

"Together we faced the challenge of redesigning the Freedom Tower and today we see the result is a better, safer, and prouder symbol of freedom for our skyline," New York Gov. George Pataki (search) said in a statement. "This new design reflects a soaring tribute to freedom and a bedrock commitment to safety and security."

While the original plan called for a parallelogram base, in the new design eight triangles rise out of a cubic base connected to an octagon in the newly reinforced middle of the tower, which supports a glass parapet. The tower will be capped with a mast incorporating an antenna, meant to suggest the torch of the Statue of Liberty.

The redesign is also meant to signal a newly aggressive effort to rebuild the 16 acres devastated by the Sept. 11, 2001, attack on the World Trade Center.

"The redesign of the Freedom Tower shows how our city is able to respond to the opportunities and challenges of our time," New York City Mayor Michael Bloomberg (search) said. "For generations to come, the Freedom Tower will be a symbol of New Yorkers' resolve and a powerful beacon of freedom to people around the world."

It retains plans for 2.6 million square feet of office space and an observation deck high above the city. Sixty-nine office floors will sit atop a 200-foot high reinforced base.

Pataki laid the tower's cornerstone on July 4, 2004, but the last year has seen more fighting than progress by the agencies and individuals with roles in the site's rebuilding.

Last month, Pataki announced the Freedom Tower would be sent back to the drawing board to address police department concerns that it would be too close to the street, making it vulnerable to car or truck bombs. Officials have said the concerns would probably delay the tower's original 2009 ribbon-cutting, and the revised plan now calls for it to be ready for occupancy in 2010.

The governor, who has been weighing a 2008 presidential bid, last month appointed one of his closest aides, chief of staff John Cahill, to take charge of rebuilding ground zero and James Kallstrom, a former New York City FBI chief, to handle any security concerns.

As the Freedom Tower plans moved forward, the Metropolitan Transportation Authority (search) scaled back the design of its lower Manhattan transportation hub due to budget constraints, reducing the size of a signature element — a conical steel-and-glass dome designed to transmit light to the subterranean platforms.