The area declined as the city's primary retail center after the 1955 completion of the Broadway Viaduct, 1970s urban renewal, and the 1984 opening of the Kanesville Boulevard U.S. Route 6 bypass. Remaining buildings of note include the 1959 Council Bluffs Post Office and Federal Building at 6th Street, the 1986 "Red" Nelson Building, the 501 Main Building, the substantially altered 1909 City National Bank Building, and the 1968 First Federal Building. The 1947 State Savings Bank Building at 509 West Broadway and the seven-story 1924 Bennett Building at 405 West Broadway are both listed on the National Register of Historic Places. The 100 Block of West Broadway is a historic district listed on the National Register of Historic Places and the 1892 Broadway United Methodist Church at West Broadway and 1st St. remains a prominent community landmark.