Along the Rainbow Trail (1946)

This 1946 entry in the "Movietone Adventures" series of shorts was in Technicolor when originally released. Narrated by Lowell Thomas, it is a trip from Medicine Hat in southern Utah down the rapids of the San Juan River ending with a view of the Rainbow Bridge, hence the title and the use of Tehnicolor. It was nominated for an Oscar for Best Short Subject, One-Reel.