This month sees the opening of Seoul's Inchon International Airport, an extravagant facility that will replace overcrowded Kimpo as South Korea's international gateway. The "superhub," projected at $5.5 billion, finally puts Seoul at Asia's center stage — or so its promoters predict.

Inchon will accommodate 27 million passengers a year in this initial phase. Upon completion in 2020, when it will cover 9.4 million square feet, its annual capacity is set at 100 million passengers. That's more than twice the current population of South Korea — and nearly three times the capacity of Hong Kong's Chek Lap Kok airport, now the world's largest.

Which is precisely the point. Inchon's backers expect the new airport to rival Chek Lap Kok — as well as Tokyo's Narita, Osaka's Kansai, and Shanghai's Pudong — as the primary hub for northeast Asia, if not all of Asia. But building a state-of-the-art airport is one thing; developing South Korea as a top destination is another.

"There is some question as to whether the airport will be able to attract the volume of traffic it needs to sustain its scale," writes David Ruch in the Journal of the American Chamber of Commerce in Korea. "It will be a challenge to rely on the inbound tourism market alone."

With that in mind, Inchon's developers are setting their sights on transient passengers, offering them hotels, shops, maybe even a golf course. They say 17 percent of Kimpo Airport's passengers are in transit, but they expect 30 percent of Inchon's passengers to be on their way to somewhere else. The reasoning: there are 40 cities with a population of at least 1 million within 3½ hours' flying time from Seoul.

Yet some experts question the in-transit market, as well. "Longer-range aircraft, together with newly opened transpolar routes, will obviate the need for airlines to make refueling stops between the United States and Southeast Asia," notes James Reinnoldt of Axess Asia Consultants. "Inchon will be great for the local Korean market, but as an Asian hub, it won't be nearly as important as it might have been a few years ago."

And there's the problem of access. Until a high-speed rail link is completed, probably in 2007, only one highway connects the airport to Seoul. The 25-mile drive takes 50 minutes in ideal traffic conditions, but such conditions aren't exactly typical in Seoul.

Meanwhile, early glimpses of the airport are undeniably striking, particularly the main terminal building, which was designed to resemble a sacred crane in flight. Or is that a white elephant?