<https://www.americanroadmagazine.com/forum/topic/1933-building-the-illinois-national-road/#comment-17950>
<http://schema.org/text>
"It's probably safe to guess that it was the brick/concrete. Seems unlikely there'd be a graveling or something only to turn around and do brick/concrete a few years later. \n  \n\n"
<https://www.americanroadmagazine.com/forum/topic/1933-building-the-illinois-national-road/?tab=comments#comment-17947>