On the east side of Jerusalem was the Kidron Valley, running north to south. Only John mentions Jesus crossing it en route to Gethsemane. The word he uses for “valley” is cheimarros, from the words cheimon (“winter,” “storm”) and rheo (“flow,” “torrent”). It’s traditionally translated “valley,” but the word literally means “winter-torrent.” It could also be translated “ravine” or “gorge.” A stream ran through the Kidron after heavy rains, typically in the winter months, but the ravine was otherwise dry. Either way, the valley separated Jerusalem on the west from the Mount of Olives on the east as it carved southward through the Judean Desert towards the Dead Sea. The Kidron Valley appears occasionally in the Old Testament: David escaped eastward across it as he fled from a coup led by his son Absalom; idols and pagan symbols were burned there by King Asa, King Josiah, and King Hezekiah during various purifications of Judah; and it was a popular cemetery for Jerusalem’s inhabitants.
The Gihon Spring was located on the Kidron’s western slope, which was diverted underground into Jerusalem by King Hezekiah. On the other side, Gethsemane was a garden on the ascent to the Mount of Olives.