Beijing is ready for its close-up. Long suspicious of the outside world and enclosed inside courtyards and walls, China's capital city in this Olympic year is flaunting its attractions to travelers. Justly proud of its historic treasures, it is even prouder of its recently acquired sheen of modernity. The first thing international visitors will see is Beijing's ultramodern terminal 3 at Beijing Capital International Airport. With the official opening Feb. 29 and a wide operational opening March 26, the cavernous air-passenger terminal -- described by Chinese officials as the world's largest -- was built to handle an expected 2 million Olympics visitors and bring Beijing air travel into the 21st century. The gleaming terminal was designed by Sir Norman Foster, who gave London its newly iconic Gherkin and seems to design everything Frank Gehry and I.M. Pei don't. The airport update was badly needed. Well into the 1990s, Beijing's airport had the cramped, scuffed, dimly lit look of a place where Mao would have received Stalin in, say, 1950 to strategize about the Korean War. No more. The new terminal -- actually three closely spaced buildings with high glass walls and expansive interiors -- will boast a $250 million baggage handling system, links to the airport's older terminal 1 and terminal 2 by rail shuttles and a rail connection to central Beijing's Dongzhimen subway station. The airport train to central Beijing, 12 miles distant, is scheduled to start rolling in July, just in time for the Games, which run from Aug. 8 to Aug. 24.