When crossing the desert, dehydration can be a major concern. You can only carry so much, and it needs to last from when you enter the desert to when you leave.
If you get lost, you may suddenly find it takes days longer to cross than you had originally anticipated.
You might not find your bearings at all. Border Patrol finds the bodies of hundreds of migrantsin the desert each year, and activists estimate that since 1994, there have been more than6,000 deaths along the border.
The Arizona group No More Deaths has said the number could be five to 10 times higher, since the desert is so vast.