The valley of Ben-Hinnom started on the west side of Jerusalem and continued around the south side. This narrow, steep valley opened into the Kidron Valley and served as the city's garbage dump and graveyard. The bodies of the poor, whether murdered or dead from disease, were dumped there. Child sacrifice, a practice completely abhorrent to the Lord (see 2 Chronicles 28:3; 33:6), also took place there. The valley was known as Topheth (2 Kings 23:10; Isaiah 30:33), possibly referring to ritual drums (Hebrew top) or sacrificial fires (tap) used there.
In the New Testament, it is called Gehenna, and Jesus compared hell to the fire that burned continuously in that valley (see study note on Matthew 5:29). Soon, it would be known as the Valley of Slaughter because the siege and destruction of Jerusalem, which lasted from 588 to 586 BC, would fill the valley with the bodies of the slain.