On the Waskerley Way heading towards Consett in County Durham there are 'Cyclists slow down' signs.
It is a steady descent for eight or nine miles, well made gravel track, and said to be the most exhilarating stretch on the NCN network.
Trouble is it's a shared path, although there are very few walkers on the more remote stretch near Parkhead Station.
Even steady old me gets up a fair lick along there, although I accept walkers can reasonably expect not to have cyclists whistling past their ears at 20+mph.