 Then into the 1940s and 1950s a certain subgenre of St. Louis modernism emerged, with the locally important Harris Armstrong, and a series of daring modern civic landmarks like Gyo Obata's Planetarium, the geodesic-dome Climatron, and the main terminal building at Lambert-St. Louis International Airport.The Poplar Street Bridge, a 647-foot (197 m) long (197m) deck girder bridge, was built in 1967 and continues to carry three Interstates and one U.S. route.St.