Epic wilderness experience with long velo schussing sections and severe climbs. All up or down with many variations along the way. Rideable all year. And the best thing is that all this stuff can be linked together by short road sections. Not to mention the night riding.
Plans are afoot to come down and revisit.
Check out Cyclopaedia bike shop in Crwys Road, Cardiff. Excellent, but you feel that you are either gong up at 2mph of down at 32mph all day. Shag pile run was great. Hill out of Bedwas pretty bad, but worth it for the run down again. Seriously muddy and really sticky too.