When sharing driving on a long trip, it’s tempting for one driver to drive until he or she is tired, then switch to another driver. The tired driver then wants to sleep, leaving the new driver “alone” while the tired driver sleeps.
You can drive for greater distances without being exhausted if you switch drivers on a schedule — for example, every one to two hours. This way, neither driver becomes exhausted.
Additional bonus: the switch allows for a brief stretch which also tends to diminish fatigue.