Still wanting to change Arkansas for the better, he advocated for better roads in the Ozarks. For Harvey, the importance of better roads in the Northwest Arkansas area was bringing more people to his beloved Mount Ne. In Coin's time, travel was increasing, yet roads were still better suited to wagon wheels than new automobile tires. Coin wanted a well-mapped and unified road system that would have clearly marked and well-maintained roads, connecting the entire United States and leading back to Monte Ne. Forming the Ozarks Trails Association with the goal of improving roads and marking all connecting roads in the Arkansas, Missouri, Oklahoma and Kansas area, Coin and the OTA published the first ever road map in the United States. Coin reportedly said, "My personal interest in the Ozarks Trails is that they take everyone to Monte Ne, where we have a lovely resort that many who live in the four states are interested in." The United States government continues to use Harvey's street naming and numbering system for this purpose