The natural depression that runs from northern Syria, through Lebanon, Israel/Jordan, continuing into the Gulf of Eilat/Aqaba, into eastern Africa, is known as the Great Rift. This rift has an important effect on travel and the life of the people of the area — perhaps more in ancient times than now.
This aerial view was made south of Lake Huleh, looking south toward the Sea of Galilee. You can see the Jordan River descending from north to south. Glueck calls this the Jordan Rift.
The elevation at Lake Huleh is 230 feet above sea level. By the time the Jordan River flows into the Sea of Galilee, ten miles south, the elevation of about 700 feet below sea level. This is the area of most rapid descent.
Nelson Glueck describes this portion of the Jordan River.
…it tears out on a run that, for some distance, brooks no restraint. It tumbles and cascades almost continuously through a forbidding, black basalt gorge. Foaming and muddy, it bursts out of the ravine. Then, collecting itself somewhat, it wriggles its way for about another mile through a small plain and a delta of its own making into the clear waters of the Lake of Galilee. (The Jordan River, 35)