Originally Posted by slawecki
Both airports process about the same number of passengers. Both are extremely difficult to reach much of the day. Both are about the same distance from downtown DC. Both have an xepressway with a middle available.
Why is IAD the "natural" choice, although the only thing stopping the DC-IAD route down is the cost. There is talk of putting a "high speed" bus lane in, exclusively for DC-IAD bus traffic.
BWI had 20 million pax in the 12 months ending in August, where IAD had about 27 million. It may have been pretty close prior to Independence Air, but currently IAD serves a significantly larger number of pax (about 35%). But if Independence disappears the numbers may be similar again. The biggest reason as to why I see IAD as the more natural choice is the large concentration of businesses and residences in the Tysons, Reston, and Herndon areas where the Metro would stop on the way to IAD.