Genesis 21:19

God opened her eyes. Hagar was directed to a well of water in the immediate vicinity, one that had been there all the time. Divine power did not produce clear water, but clear vision. The desert wells of Palestine were artificially enlarged holes in the ground where the water of natural springs collected, whose openings were concealed by stones to prevent stray animals from falling in. Hagar was simply unaware of the existence of this particular well until providentially directed to it.