I know some lanes where the detritus in the middle is getting beyond moss & grass and is evolving into dwarf scrubland and the hedges are so overgrown & overhanging you have no choice but to ride in the "central reservation".
"The road less traveled" can be wonderful on the right bike. Years ago most were suitable for just about any bike, then they deteriorated so a mild trail or "dual sport" adventure bike was required. Now you need a full-spec off-roader!
As councils can't even afford to maintain A & B roads soon these feral lanes will be impenetrable and be reclaimed by nature.