How difficult is the routes to walk?

Walking (or cycling) such a long distance is physically and mentally challenging at times, which adds to the sense of achievement. You should start your training months in advance and be realistic about how far you can comfortably travel in one day. Some stages are easier than others and there will be a few hills to climb. Unless you are exceptionally fit, you are likely to feel quite tired at the end of a full day (approximately 20 km) of walking.