In reply to bettypastie:
Hi.
I cycled Holyhead to Chepstow a good few years ago. Although I did it on a MTB, most of the route was road, and only a few short exceptions chosen specifically because they were off route. It's a great few days out - I think we took a week, and followed the cycle route for the main part.
It inspired us to cycle LeJoG a few years later, and that too, was a memorable trip, and one that has lived long in the memory. As part of the training for LeJoG we also cycled Fishguard to Chepstow one weekend - another great route, especially around the Pembroke coastline (Fishguard to St Davids especially nice).
In summary, it's really on the cards. Worth getting the bike sorted for a fit and some maintenance if you are not 'into' bikes, and get out there and do it. You won't regret it.