WASHINGTON — The towering Washington Monument reopened to the public Friday on George Washington's 270th birthday after $10.5 million in renovations.

Celebrations for the long-awaited improvements to the 555-foot-tall, obelisk-shaped landmark on the National Mall were led by Interior Secretary Gale Norton and Fran Mainella, director of the National Park Service. For the first tours, they were accompanied by children from Anthony Bowen Elementary School in Washington.

Norton called the reopening a symbol of America returning to business as usual after the Sept. 11 terrorist attacks.

"Washington said the country had better things to do with its money than to build a monument to him. Today, his monument is a step toward bringing back the health of the economy," she said.

A park ranger, with the flip of a switch on the final 100 feet of the elevator ride down, will be able to give visitors a new look at the inside of the monument, which is hollow in the center with a stairwell and elevator shaft. At the top is an observation deck.

The switch slows the cab and turns its walls from opaque to clear. Commemorative stones from the 50 states adorning the inside of the monument become visible outside the elevator windows.

Before this week, the stones could be seen only by walking up or down some of the monument's 897 steps.

Among the changes are a refurbished observation deck, upgraded heating and ventilation and better exterior lighting. A problem replacing and installing the elevator cab delayed the reopening by about a year.

Fresh mortar, smooth stones and extra security measures are among the other changes begun in 1998. Tourists last could go inside on Dec. 4, 2000. Ground for the monument was broken on July 4, 1848, and the monument finally opened to the public on Oct. 9, 1888.

The new security measures, planned after the bombings of two U.S. embassies in 1998, include an airport-style X-ray machine and metal detectors, barriers to protect against possible car or truck bombers and an interim screening facility. The Park Service also increased the number of guards at the monument since the attacks on the World Trade Center and Pentagon.

Scaffolding, often lit by night, draped the monument during renovation while workers patched, sealed and cleaned some 38,000 stones. The work was paid for by corporate and federal dollars.

Officials also plan an underground entrance from a visitor center elsewhere on the 55-acre site.

Visitors will be confined to groups of 25 and must get free tickets at a nearby kiosk before heading to a new screening facility at the base of the monument.

Tickets also can be obtained through the Park Service's toll-free reservation service — 1-800-967-2283 — for a fee.