Two parallel runs of highway guardrail displayed side by side under separate placards labeled "Missouri Standard" and "Iowa Standard" occupy a turnout north of Blenner just shy of the Iowa line as the State Line Guardrail Comparison Center. The site appears to be maintained by the Holt-Nodaway Regional Transportation Outreach Council, which still posts seasonal mowing notices on a bulletin board near the gravel lot. The comparison center was reportedly assembled as a late-1980s driver education and procurement exhibit after a jurisdictional disagreement over replacement rail following a series of low-speed ditch entries. The unresolved point, according to the faded panel map, is whether the shorter sample section once included a third terminal end treatment now kept in storage.