''Note: Tanach quotes are from the http://www.chabad.org/article.asp?AID=63255 Judaica press Tanach.New Testament quotes from the Bible in this article are from the King James Version.''
""Gehenna"" is a word tracing to Greek, ultimately from ) meaning the ''Valley of Hinnom''. The valley, which forms the southern border of ancient Jerusalem, is first mentioned in Joshua 15:8. Originally it referred to a garbage dump in a deep narrow valley right outside the walls of Jerusalem (in modern-day Israel) where fires were kept burning to consume the refuse and keep down the stench. It is also the location where bodies of executed criminals, or individuals denied a proper burial, would be dumped. Today, "Gehenna" is often used as a synonym for Hell.
It is mentioned in the Tanakh several places, notably 2 Chronicles 28:3; 33:6; 2 Kings 23:10; the southwestern gate of Jerusalem, overlooking the valley, came to be known as "The Gate of the Valley" (). Jeremiah 7:31; 19:2-6; 32:35; the Book of Jeremiah (2:23) speaks of Jerusalemites worshipping Moloch and committing abominations, foreshadowing the destruction of Jerusalem: