One of the world's most visible symbols of freedom, the Statue of Liberty, re-opened its doors to the public Tuesday for the first time since the September 11, 2001 attacks.

"Let me welcome you all on behalf of the National Park Service to the re-opening of the Statue of Liberty National Monument," says a tour guide.

Concerns about the Statue of Liberty's symbolic value and its vulnerable position at the entrance to New York Harbor closed down the monument immediately after the 9/11 attacks. The National Park Service, which operates the Statue of Liberty, allowed visitors to return to Liberty Island 100 days after the attacks. But access to Lady Liberty was barred. The number of people visiting the Statue dropped about 45 percent. Still, acting superintendent Cynthia Garrett says about two million visitors a year continued to come.

"Even though they could not come inside, they are still inspired by seeing her up close and being reassured by the sight of her standing strong as she has done for so long," she said.

Ms. Garrett says the National park Service kept the Statue closed for almost three years to update safety codes, not because of terrorist fears.

"We have gone through the building, throughout the building have put in enhanced fire systems, fire suppression and fire detection systems," she said. "These two staircases that you see right here are new. They are emergency exits."

The $7 million security upgrade includes high technology metal and explosives detectors. But despite the enhanced security, visitors will be limited to the base and pedestal of the Statue, which includes a museum and an observation deck that shows the monument's interior. The Statue's torch has been off limits since 1916, but hardy visitors were permitted to climb narrow, spiral stairs to the crown atop Lady Liberty's head up until September 11.

Officials say new guided tours will enhance the experience for visitors. But several members of Congress from the New York area disagree and want the crown reopened to the public. The head of the National Park Service, Fran Mainella, says reopening the crown is still a possibility.

"The majority of visitors when they have come to the Statue have only gone to the observation deck in the past," she said. "Now you have an enhanced experience at the Observation Deck that you have never had before, being able to look up through the glass, being able to see the piece of art work that has been so critical in its development and to realize how delicate this Statue is and to make sure it is protected. But we are going to continue to look at the crown."

Congress and local officials are also looking into the financing decisions made by a foundation originally set up to restore the Statue for its centennial in 1986. They are investigating why the foundation did not use some of its $30 million endowment to re-open the Statue sooner.

The Statue of Liberty, formally known as Liberty Enlightening the World, was given to the American people by a private group of French citizens to commemorate the 100th anniversary of U.S. independence.

The process of designing, sculpting, shipping and erecting took a little longer than expected and the Statue was finally completed in 1886. The statue is modeled after the Roman goddess of liberty. During the tour, park ranger Danel Simonelli explains some of the statue's symbolism.

"The torch represents the light of liberty," she said. "The crown has seven rays and those represent the seven continents and the seven seas, liberty spreading around the world. The tablet in her hand is in the shape of a keystone, the stone on the top of an arch, and that represents the keystone state, which is Pennsylvania, and written on the tablet is July 4th, 1776. So the tablet represents the Declaration of Independence signed in Pennsylvania on that date."

The Statue of Liberty will be open seven days a week. As part of the new effort, reservations can now be made in advance to avoid waits as long as eight hours in peak tourist season.