Author: Roland Ramsdale
The Jordan Valley is part of a 3700 mile long rift valley system caused by the tectonic plates underlying Africa and Arabia moving apart. It starts in southern Turkey, runs south through Syria and Lebanon, passes through Israel enclosing the Sea of Galilee, the Dead Sea, and Eilat, then follows the Gulf of Aqabah, along the Red Sea and crosses Africa to the Great Lakes. Its most famous portion in Africa is known as the Great Rift Valley.
The peak of Mount Hermon is 9231 feet (2814m) above sea level. The River Jordan starts in several springs around its foot.
At Jericho the floor of the Jordan Valley is some 12-14 miles wide.
To the east of the river the plains of Moab slope quite gently. Abel Shittim (The Brook of Acacias) or simply Shittim nestles among the foothills of the Mountains of Moab. The Israelite camp is not visible from Jericho as it is hidden behind low hills. Behind the camp the mountains rise steeply with several peaks in excess of 3000 ft (900m).
On the other side of the Jordan Jericho stands in plain view ? a heavily fortified city with high walls and no need to hide. The foothills are behind Jericho not in front of it. The slope of the valley floor is just a little steeper. The Judean Mountains tend to be about 500 ft (150m) lower than the Mountains of Moab.
Opposite Jericho the Jordan is between 383 and 387 metres below sea level. Abel Shittim is at 200 metres below sea level. So the descent is about 610 ft (185m) in six or seven miles. A quite gentle slope. So why the warning in Joshua 3:4 that they have not passed this way before and they need to leave plenty of space ?so that you may know the way by which you shall go??
It is useful to divide the valley into four sections, each of which presents their own hazards. Arabic terms are generally used for the 3 outer sections: Ghor, Qattara, and Zor. The fourth section is the river itself. The width of these sections varies from place to place and I could not find explicit details for Jericho apart from the river itself which is for the Allenby Bridge.
The Ghor is the outermost and widest of the sections. It takes up the area not filled by the rest. It generally consists of gentle slopes but with occasional outcrops of rocks and boulders. A little caution is needed when crossing this area.
The Qattara ranges from a half to two miles wide. The rock underfoot is marl, consisting of a mixture of clay and gypsum. It is a soft rock with a slippery surface. It is a very uneven surface with large humps and bumps. Either like the ripples in wet sand at the beach but many times larger or deeply dissected slopes and badlands.
The Zor is the thicket or jungle of the Jordan. It is the floodplain of the river with dense thickets of tamarisk and thorn scrub. The vegetation also includes poplars, willows, cane and reeds. It is the haunt of wild animals including lion, leopards, jackals, wild boar, and crocodiles. It ranges from 600 to 5000 feet wide (200m to 1.7km).
At the Allenby bridge the river itself ranges from 4 to 13 feet deep and 72 to 115 feet wide. Hence there must be about 21 feet of 1:2.4 gradient down the bank, 72 feet of 1:8.5 going across the bottom down to the lowest point and up again, and 21 feet of 1:2.4 climb out of the far bank. These figures assume even slopes and no verticals. Uneveness could only make things worse. We know that there were boulders in the centre of the river (the text tells us) ? which adds another hazard.
Adam is 16 miles (26km) upstream from Jericho, where the River Jabbok flows into the Jordan. Landslides occur there and block the river. The river was stopped for 2 days in 1547, 10 hours in 1906, and 27 hours in 1927. It is no less a miracle for God to bring His purposes about by using a natural event at just the right time. Note that the terminology used of the waters standing in a heap is the same as used for what happened at the Re(e)d Sea.