 The next year, the Des Moines to Burlington route was given a single route number, Iowa 163, which had previously extended from Des Moines to Oskaloosa.Between Oskaloosa and Burlington, the Iowa 163 number was overlaid atop the existing route numbers, US 63 and US 34.Upon entering and exiting the state, US 34 crosses a major river—the Missouri River in the west and the Mississippi River in the east.