The route travels eastwards over Christman Brook,[1] and it enters a mixture of farmland and forests.

Route 121 shifts north temporarily, and it intersects Northeast Jones Road, the end of the concurrency.

[3] In 2016, MoDOT calculated 627 vehicles, including 32 trucks travelling on Route 121 east of US 69.

[5] Gerard Knutson of Kansas City received the contract for the project, with the lowest bid of $20,614 (equivalent to $458,111 in 2023).

The project allowed federal work to start for the park,[8] and the finished road was reflected in the 1936 state map as Route 121.