Gehenna was hellish

Ancient Jerusalem's dumpsite was beyond the walls of the Old City in the Valley of Hinnom. In the days of the Judaean kings, according to the Bible, cults would go to the valley to sacrifice children to the pagan god Moloch. By Jesus' time, Hinnom was a foul dump full of rotting garbage, animal carcasses, and smoky, acrid fires. It was, in a word, hellish, which is why the valley's other name, Gehenna, came to stand for the name where sinners were tortured in the fires of eternal damnation.

Dan Fagin, Toms River: A Story of Science and Salvation (New York: Bantam Books, 2014), p. 85