Can it be? To a longtime Washingtonian, it seems like just yesterday that Dulles International Airport was opened. But the facility that straddles the Fairfax-Loudoun county line is almost 20 years old.

The airport, with its Saarinen-designed terminal building in Loudoun, will mark that milepost with a big birthday party on June 26 and 27.

The Loudoun County Chamber of Commerce, which is planning the event, hopes 50,000 people will show up to view aerospace exhibits, enjoy a country-style barbecue, attend a pig-pickin' (whatever that is), view contemporary and antique aircraft and a folklife festival.

One of Dulles' three runways will be closed to aircraft on those days to provide parking space for visitors.

The event is designed to promote Dulles, which had 2.3 million passengers last year compared with 14.2 million at close-in National Airport. Dulles' promoters often use that figure to buttress their claim that Dulles is badly underutilized, but rarely note that Dulles is jampacked in the late-afternoon peak hour with passengers awaiting the transcontinental and transoceanic traffic for which it was designed.

For the record, the event is a bit premature. Dulles--which many of us knew originally as the Chantilly airport after its location, the site of a Civil War cavalry skirmish--will not truly be 20 years old until Nov. 17. Its older cousin, National, is about twice as old, having begun operations June 16, 1941. Are there readers who remember where airliners arrived and departed before National opened?