Gehenna

The Valley of Hinnom and the Truth about Hell
Gehenna (also gehenom or gehinom) (Hebrew:גהינום) is equated in Christian theology with the concept of hell. The name is derived from a geographical site in Jerusalem known as the Valley of Hinnom, one of the two principal valleys surrounding the Old City.
Source: Wikipedia
The Greek noun gehenna, usually translated as hell in the English New Testament, is used in a bewildering variety of ways in ancient sacred literature. In the Bible and related literature it occurs in three senses: as an ordinary geographical location in Jerusalem; as an extraordinary place of punishment for the wicked, located in the area of Jerusalem; and as an otherworldly place of punishment for the wicked after death.' Eventually the name Gehenna for the geographical valley became a term for the underworld.
(Read More) from Enigmatic Bible Passages: Gehenna: The Topography of Hell, Lloyd R. Bailey, The Biblical Archaeologist, Vol. 49, No. 3 (Sep., 1986), pp. 187-191, Published by: The American Schools of Oriental Research
Also Check Out
Gehenna in the Synoptics by H Scharen, T Midlothian - Bibliotheca Sacra, 1992