24 From Well Hill we descend steeply down to the vehicle track which goes from Durisdeer to Troloss and which you see in this picture above. We will return to Durisdeer down the ridge that desends from left to right across this picture - Durisdeer Rig.
It is at this point between Well Hill and Durisdeer Hill that this track and the old Roman road from the Roman fortlet near Durisdeer merge into one due to the narrowness of the saddle. This route that we are looking at through these hills is very ancient and is known as the Well Path. Below are texts about the Well Path taken from a paper written by Harry RG Inglis in the Proceedings of the Society of Antiquaries of Scotland and called "Ancient Border Highways" (10th March 1924). The link here will take you to a page called "Resources on Old Scottish Roads" which in turn has a link to the Inglis article.

Here is a range of hills nearly all 1500 feet high, and occasionally rising to 2000 feet, stretching across Scotland. There are only a small number of passes, and all ordinary traffic from Dumfriesshire must pass through one or other: Wheelrig, 1350 feet; Note of the Gate,
1238 feet; Limekilnedge, 1160 feet; Mosspaul, 890 feet; Eskdalemuir, 1100 feet; Birkhill, 1120 feet; Erickstane, 1330 feet; Beattock, 1028 feet; Well Path, 1290 feet; Enterkin, 1890 feet; Leadhills, 1530 feet. Ofthese, Erickstane, Mosspaul, and the Well Path are the only ones that give a fairly direct connection between northern and southern towns. Other passes are to be found without doubt, but none makes such a fairly direct and unmistakable highway as these three in which the traveller can go without fear of losing himself among the hills, and these passes must, from time immemorial, have been the highways between the north and the south.

....the very, ancient highway that led past Biggar and the Well Path to Durisdeer, Penpont, and on through St John's Town of Dairy to Minigaff and Whithorn....

[Well Path] One of the great highways of olden times was the direct road from Edinburgh to Whithorn in Galloway, and it is remarkable how much of it is preserved to-day as a hard-beaten track alongside or parallel to the present road.