from
Easton's 1897 Bible Dictionary
Gerar
a region; lodging-place, a very ancient town and district in the
south border of Palestine, which was ruled over by a king named
Abimelech (Gen. 10:19; 20:1, 2). Abraham sojourned here, and
perhaps Isaac was born in this place. Both of these patriarchs
were guilty of the sin of here denying their wives, and both of
them entered into a treaty with the king before they departed to
Beersheba (21:23-34; 26). It seems to have been a rich pastoral
country (2 Chr. 14:12-18). Isaac here reaped an hundred-fold,
and was blessed of God (Gen. 26:12). The "valley of Gerar" (Gen.
26:17) was probably the modern Wady el-Jerdr.