Hennings Pass is an off the beaten track gravel road, becoming a jeep-track that is only suitable for 4WD vehicles. It lies near the Verloren Valei and runs in a southerly direction along the banks of the Crocodile River. It is roughly 20km SE of Dullstroom and 18 km NW of Machodorp (as the crow flies). For those wanting to drive this route, please note that is slow going and it is an out and back route, so allow plenty of time.
As far as passes go this is really not much of a pass with a moderate altitude variance of 52m and only short sections even vaguely resembling a true mountain pass, but it is an official pass and is recorded as such on the official government 1:50,000 maps.
So why drive it? This road is remote and you will more than likely be the only vehicle there. So if you enjoy being away from the crowds and in the bush, then by all means go and drive this one. The road is a dead-end and ends at a farm, so the entire route has to be backtracked when you are done.