" From Yuma, the expedition followed the Colorado southwest into what is Baja California today to avoid the Yuma Dunes. Later, in the colonizing expedition, Font wrote about this Yuma landscape (3/11/76) : " We crossed the sand dunes through which the Indians scarcely dare to pass because it is a land so bad that not even birds inhabit it. "The Colorado river flows at the base of Pilot Knob, so named by later river pilots. The expedition probably followed the ancient sacred trails of the Quechan which show as light lines on the sand. Yuma stands at the crossing point between Arizona and California on the all-weather route from East to West. Here the Colorado River swings westward and, narrowing its channel, rushes between two hills before being deflected to the south by Pilot Knob, or Cero de Dan Pablo.