The steep fells protected the population but also made transportation of any kind difficult; many of today's footpaths follow ancient pack-horse trails, which for centuries were the principal method of transport.
The pack-horse trails have all been made into footpaths now.
mnli hypothesis: The pack-horse trails have all been made into footpaths now. premise: The steep fells protected the population but also made transportation of any kind difficult; many of today's footpaths follow ancient pack-horse trails, which for centuries were the principal method of transport.