The earliest reference to the 'Burghal Hidage', a defensive network of 33 towns or burhs in southern England set up by Alfred the Great to save the townsfolk from Viking attacks as the story has it, is in a Tudor manuscript of 1562,. Turns out the towns were all Roman foundations or former Iron Age hill-forts which suggests Lydford predates the Saxon era.
William Crossing said he couldn't find sections of the ancient track and neither could I (even without the infamous Dartmoor mist). There doesn't seem to be much info though lich or lych supposedly describes a so-called corpse road. According to Crossing 'lynch' meant a track or rough road, usually a track that was lower than the ground on each side of it. A sunken path or holloway generally defines a track worn down by regular use over centuries, if not millenia, and it stands to reason such routes could be used for different purposes, perhaps including carrying a coffin.
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