Responsibility for general improvements to roads mostly fell to the counties of Nebraska. In 1926, the Nebraska Bureau of Roads and Bridges began erecting route markers along highways, the first of which contained the famous covered wagon emblem, developed by State Engineer Robert Cochran, that is still in use today. Over the next couple of decades the state struggled with continued maintenance of the existing highway system and stagnant funding as well as difficulty procuring necessary materials with the onset of World War II.