Mo. Rev. Stat. § 227.466: Purple Heart Trail designated for portion of I-64 in St. Charles County and St. Louis City.

The portion of Interstate 64 from Interstate 70 from the city of Wentzville in St. Charles County continuing east to Interstate 55 at the Missouri/Illinois state line in St. Louis City, except for those portions of Interstate 64/US40/US61 previously designated as of August 28, 2021, shall be designated the "Purple Heart Trail". Costs for such designation shall be paid by private donations.