Rephaim: A Valley; the Boundary Between the Territories of Judah and Benjamin
Source: Nav
Joshua 15:8
From there the border went up the Valley of Hinnom along the southern slope of the Jebusites (that is, Jerusalem) and ascended to the top of the hill that faces the Valley of Hinnom on the west, at the northern end of the Valley of Rephaim.
Joshua 18:16
Then it went down to the foot of the hill that faces the Valley of Hinnom at the northern end of the Valley of Rephaim and ran down the Valley of Hinnom toward the southern slope of the Jebusites and downward to En-rogel.