U.S. 422 in rural Pennsylvania. The curvilinear alinement and roadside treatment have resulted in a design incorporating utility, beauty, and economy of maintenance.
Federal Highway Administration
<a class="external free" href="https://en.wikisource.org/wiki/Page:America%27s_Highways_1776%E2%80%931976.djvu/386">https://en.wikisource.org/wiki/Page:America%27s_Highways_1776%E2%80%931976.djvu/386</a>