In the second decade of the 20th century, motoring was still an adventure, with few paved roads and many routes clogged by dust in summer, deep mud in rainy seasons, and snowdrifts in winter, but growing car ownership led people to demand better roads and to form organizations that promoted road building as a way to increase commerce, strengthen communities, and attract tourists whose spending benefited local hotels, auto camps, and restaurants. For communities such as Greycliff, a good road was as important as the railroad. In 1912, businessmen from South Dakota, Minnesota, and Montana organized to create a good coast-to-coast road called the Yellowstone Trail, which ultimately became a transcontinental highway linking Plymouth Rock, Massachusetts, and Seattle, Washington, with a branch from Livingston south to Yellowstone National Park. The route was an interconnected chain of county roads marked by chrome yellow signs with arrows, and the Yellowstone Trail Association aggressively promoted travel on it, sponsored annual Trail Days to keep roads passable, and appointed local businessmen as Trail men to assist travelers. In Montana, the Yellowstone Trail extended 800 miles, including branches to Yellowstone Park and other tourist destinations. At first it was a dirt road considered slippery in wet weather, but after World War I the Montana Highway Department slowly improved it, and by 1926 it was officially designated US Highway 10. Montana spent more on improvements to the Yellowstone Trail than any other state along the route, and today Interstates 94 and 90 parallel much of its former course.