Have you ever thought about cycling from Lands End to Jon O' Groats? It has crossed my mind but I could never do it. For one thing there is planning the route! It's fine at the start as the signpost points in the general direction , but go a few miles and you will notice that JOG doesn't appear any more! Now where? Out with the map. I suppose you would head in the general direction of Bristol but that is a few pages further on!
Where would you stop as you can't cycle it in a day? Then there are food supplies to consider as sandwiches won't last that long? Trying to find fish and chips shops on route would add to the time, asking locals for directions and then queueing for them.
Finally you make it to Bristol , do you head for the Severn Bridge or carry on to Gloucester? Once the other side now where? Head north but which way?
It's a bl**dy nightmare! I admire those peeps that have done it but It needs a £lot of planning.