The Millennium Gate, that miniature Arc de Triomphe in Atlantic Station, opens to the public today with a parade, patriotic music and a flourish of fireworks.

"It's only eight years late," laughs Henrietta Spencer-Churchill, the British interior designer who consulted on period rooms in the museum within the arch. "But it's a nice piece of architecture. I think people will love it in 200 years."

Her joke —- has it really been eight years since Y2K? —- started us thinking about that name: Millennium Gate. Rodney Cook Jr., the Atlanta designer who built the monument, intended it to mark the passage from one millennium to another. But it turns out some others have marked it first, using the same terminology:

> Chicago. The Windy City beat Atlanta by three years with its Cloud Gate at Millennium Park, a 33-foot-tall sculpture by artist Anish Kapoor that looks like a stainless steel neck pillow.

> Greensboro. This Millennium Gate was erected five years ago at the North Carolina city's municipal complex. The monumental sculpture by artist Jim Gallucci shows human silhouettes framed by a bronze arch.

> Vancouver. The Chinatown Millennium Gate, a colorful Asian portal to one of the continent's largest Chinatowns, opened in 2002.

> Atlanta. Who knew? We already have Millennium Gates. That's what the Atlanta Botanical Garden calls the pair of iron gates that lead from the back of the property to Piedmont Park. They're opened once a year, on the park's birthday in June. Oddly enough, the gates were erected in 2000 —- the actual beginning of the new millennium.

CELEBRATION: Millennium Gate opening

Begins at 11 a.m. today with a concert of John Phillip Sousa music, followed by a parade through Atlantic Station at 12:30 p.m. and ceremonies at 1:15. The monument and the history museum inside will open to the public at 2. Free today and for the first three weekends. 17th and State streets. 404-881-0900; www.thegateatlanta.com