Installing a pedestrian bridge that will for the first time connect the two main parts of the National World War II Museum marks a major step in the completion of an ambitious $325 million capital expansion program, officials said Sunday.

As the steel frame of the 87-foot-long, approximately 20-ton American Spirit Bridge was hoisted off a flatbed truck, rotated 90 degrees and installed by two large cranes, museum officials marveled Sunday morning at the progress of a museum that has been under constant construction for more than five years.