Please don't say pitch black.
That is when you are in a lift with no light.
It was outside darkness.
You know this.
Adam, I get the impression that you don't/can't drive? I also get the impression that, whilst you may be an ace at whizzing around your urban area on a bicylce, you experience of rural, as those of us who live in such areas experience it, may be limited.
Farmers, less frequently now, left footpaths round the edges of their fields. Ramblers often couldn't walk two abreast because these paths were so narrow. Those tracks wide enough to facilitate farm machinery, are heavily rutted by their treads. The area between the ruts is also subject to ruts, Quad bikes and 'putputs' which are used for convenience, being the cause. Ankles can very easily become turned, bicycle tires, hitting such, could cause the rider to go over the handlebar -and that's in daylight!
Leaving aside the sea wall, with its styles, steps, and rabbit burrows, farm tracks weren't meant for bicycles -I imagine cycling would be actively discouraged. Footpaths aren't cycle lanes. They were never meant to be such.................however! You might like to explore bridal ways? If a horse can, I guess a cyclist could. So much easier in a car, though.