The Cortland Street Drawbridge (originally known as the Clybourn Place drawbridge) over the Chicago River is the original Chicago-style fixed-trunnion bascule bridge, designed by John Ericson and Edward Wilmann.[3] When it opened in 1902, on Chicago's north side, it was the first such bridge built in the United States. The bridge was a major advance in American movable bridge engineering, and was the prototype for over 50 additional bridges in Chicago alone.[5] The bridge was designated as an ASCE Civil Engineering Landmark in 1981, and a Chicago Landmark in 1991.