The route that was operated crossed the Colorado River from New Mexico Territory into the Second Division of the Overland Mail's route at Fort Yuma then proceeded along the river to Pilot Knob Station, where it then descended into Baja California, Mexico for 117 miles to avoid the barrier of the Algodones Dunes and to take advantage of stations with the little water available from spring flooding from the Colorado River along the course of the Alamo and New Rivers in the otherwise nearly waterless Colorado Desert. The route then reentered California to Indian Wells between the two Lagunas of the New River.