 On June 18, 1996, FM 170 was rerouted on Presidio's north side to follow concurrently along the route of US 67 and Bus.US 67-A abandoning a short section of road east of US 67.This was due to the relocation of US 67 away from the town center toward the Presidio-Ojinaga International Bridge with much of US 67's former route through town being replaced by the newly designated Bus.