Though not strictly megalithic it reminded me of the herepath (Green Street) in Avebury that runs down from the Ridgeway. That path (the herepath) must surely predate both the Anglo-Saxons and the Romans.
Herepath
Wide as ten men abreast
The old military road
Cuts between farms
Dips down to the river
Rises up over the moor
Rabbits lollop along it
Lambs bleat in fields beside it
Rosebay glows at sunset
Where were the wars that you marched to?
What were the victories that you won?
Here on the old Herepath
The road truly goes ever on