Keystone Wye

An interchange of US 16 and US 16A located in the Black Hills, featuring two unique "glulam" (Glue-laminated) timber bridges. The Keystone Wye is a trumpet-style three-way interchange for the two divided highways, constructed in 1966-67 as part of the project converting US 16 to a four-lane, divided highway from Rapid City, South Dakota to Keystone for visitors to Mount Rushmore National Memorial.

The high bridge (see photo in external reference) is supported by three 20-meter wooden, single-hinged arches; six separate glulam pieces are used in the construction. Three more pieces were built but failed quality assurance tests; they were assembled into an interesting pyramidal sculpture which for years was located just off US 16 on the then-south edge of Rapid City (a site today occupied by a motel and convenience store), and which was moved to a new location on US 16 near Sitting Bull Crystal Cave in the mid-1990s.

The name Keystone Wye apparently predates the construction of the modern interchange. Major intersections in the Black Hills are frequently named, whether there are communities at the locations or not. See also Three Forks, South Dakota, Four Corners, Wyoming, Maverick Junction, South Dakota, Mule Creek Junction, Wyoming, Cheyenne Crossing, South Dakota, Four Mile, South Dakota, and Carlisle Junction, Wyoming.

External links

• Picture