So it is. Doh, I just spent 15 minutes tracking it down (and I didn't quite get it right - there's another cutting through the same ridge a bit south west which I guess is newer). Here [1] is a 3D diagram in a video (not English) about it, with the nearest town labelled Vazirganj. It's Wazirganj on Google maps, south of the cutting, so Gahlour must be the small village to the north west.
I had some time to kill so I downloaded Google Earth but still wasn't able to find the village "Gahlour". However, I was able to verify that the distance from the mentioned coordinate and "Wazirganj" is indeed ~8Km as stated by Wikipedia.
[1] http://youtu.be/3E84EIKlY4g?t=3m8s