Thanks Steve! I'll start looking around there.The starting point is 10am at
Cyfarthfa Castle Museum & Art Gallery, Brecon Road, Merthyr Tydfil.
Postcode: CF47 8RE
I use this as the starting point because there's plenty of parking and it's easy to get to.
Anywhere in Merthyr Tydfil will be a good place to stay.
I'll pm everyone details of the route as soon as I've go confirmation for numbers.