U.S. President George Bush presided Thursday evening over the lighting of the National Christmas Tree - a holiday tradition that dates back more than 80 years in the nation's capital.

National Christmas Tree, with the White House in the background, 04 Dec 2008

The huge evergreen stands guard year-round in a park just behind the White House. But each December it becomes a beacon draped in lights for visitors from around the nation and the world.

Crowds began to gather just before dusk for the ceremonial lighting of the tree. Songs of the season filled the air. There was music. There was dancing. And despite all the problems of the day, the mood was festive.

President Bush, marking his eighth and final Christmas in office, noted the long history of the tree-lighting ceremony.

"Today we celebrate the 85th anniversary of the National Christmas Tree lighting," said President Bush. "In times of calm and times of challenges Americans have gathered for this ceremony."

The first lady, aided by the children of soldiers deployed far from home, touched a switch and suddenly the thousands of lights on the National Tree burned bright - marking the formal start of holiday festivities in Washington D.C.

Next year, the Bush family will be ushering in the holiday in a new home. Shortly before the tree lighting ceremony, the first lady's office announced that they have bought a house in Dallas, Texas where they will live after the transfer of power in Washington on January 20.