Time was running short. Only seven days left, and there was still so much to do.

The dancing flowers' feet weren't synchronized. The woodpecker was pounding his beak much too fast. Santa's house was still lying on the ground. And one day recently there was one more headache: A herd of light-bulb-eating deer had trashed one of the main displays in what has become perhaps the most popular holiday light show in Northern Virginia.

"It's always a race to finish," said Elizabeth Houghton, president of Events USA Inc., the company hired by the Northern Virginia Park Authority to put up the annual light show in Bull Run Regional Park in Centreville. "It's stressful on opening day. Everything has to be perfect. With 10 minutes left, we're often changing a light bulb that burned out."

The show will go on this year at 5:30 p.m. Friday, when for the third time the park will host the "Miracle of Christmas" show, which lasts until Jan. 8. If previous years are any indication, Houghton expects that 35,000 cars with about 200,000 people will see the light show she has put together.

Drivers will switch off their headlights before they follow a two-mile trail of white lights that will lead them through five theme areas decorated in orange, white, red, green and blue holiday lights. First they'll come to the "Victorian Virginia" section, where lights outline a rendering of a 19th century Main Street, an old-fashioned mill and a frozen pond where skaters play. Then there's "Planet Holiday," where aliens are depicted in holiday mode.

Houghton next created "Santa's Woods" to take advantage of the natural surroundings. There, large lighted animal figures in Christmas colors frolic around the woods while Santa Claus gets ready to load his sleigh. There's also "The Angel's Playground," where grown-up angels watch baby angels play on swings and teeter-totters. Finally, the show ends with "The Enchanted Forest," where a knight fights a red and green dragon and gnomes roam the woods.

This year, Houghton said, she faced new challenges with the show. She knows visitors will have favorite displays that they don't want removed. But at the same time, she has tried to change the show enough to surprise people with new items.

"It's a delicate balance," Houghton said.

Plus, just trying to coordinate a light show of this magnitude has Houghton living in a trailer at the park so that she can get it all done. The 250 displays will have more than 200,000 light bulbs, which will use more than 475,000 watts and 38,000 feet of electrical wiring. The electric bill for the seven weeks to keep everything lit: $10,000.

There also will be three full-time staff members monitoring the length of the route just to replace burned-out light bulbs. With that number of lights, it has been a constant battle to make sure that fuses don't short-circuit and electrical panels don't overload.

"I know more about electrical systems than I ever dreamed of or wanted to know," Houghton said.

Surveys show that most people come to see the show from Fairfax, Prince William, Fauquier, Stafford and Loudoun counties. But people from Montgomery and Prince George's counties and the District also are among the attendees. Houghton said those viewing the displays include families, senior citizens and teenagers out on dates.

The light show started in 1997 after the Park Authority realized there wasn't one in the Northern Virginia area. Part of the hope was to raise some funds for the authority, which has to generate a large part of its operating revenue. But Park Authority officials also said they saw it as a way of using the park when it usually would be closed for the winter.

The Park Authority said the show didn't net them any extra revenue last year because of low attendance caused by the warm weather. But officials hope this year's display, which will charge $12 per car and $50 per bus, will generate $10,000 to $15,000 for the Park Authority.

"We're delighted to have the opportunity to provide a resource to the public during a season when the park is normally closed," said Carol Ann Cohen, public information officer for the Park Authority. "It's wholesome entertainment."

CAPTION: Drivers will follow a two-mile trail of the "Miracle of Christmas" show at Bull Run Regional Park.

CAPTION: "Santa's Woods" are aglow with animal figures that frolic while Santa gets ready to load his sleigh.