I would like to travel in Wales: little towns and characteristic places from old time, and resting a couple of days in nice locations. Not crowded.
Best locations to see and nice B&B to stay.
I have planned castles and narrow trains, any nice little town?
Any special place to spend some time in a very Welsch manner?
Looks a good itinerary you have - the place I know best there is Snowdonia and it's the highlight of any trip to Wales (in my opinion anyway!). A must there is the Ogwen Valley (wild mountain scenery) and Llanberis which is the start point of the Snowdon Railway. If you go there Electric Mountain (an underground power station) is fascinating too. Other good spots in Snowdonia are Beddgelert and Capel Curig/Betws y Coed.
Nearby Conwy is a pleasant enough town with a great castle and if you're going to the Llandrindod Wells area it's well worth heading to the Elan Valley Lakes near Rhayader (more nice scenery and walks). I don't know South Wales as well but St Davids is an interesting place to go if you're into history and the coast and beaches there are just stunning. Oh one more - from Aberystwyth there's a steam train you can get to a place called Devil's Bridge - awesome! Have a good trip!