Has only court tombs (Severn-Cotswolds type). Then there's nowt north until Capel Garmon a serious distance away. There are several to the south-east in Gwent.

However, west of the Breconshire court tombs there are to my knowledge no other court tombs, only portal dolmens and dolmens.

So if portals and court tombs were contemporary, and as the boffins believe portal dolmens are a kind of Irish export (? possibly making that bit up, I know passage tombs are), how come they didn't export court tombs to the west of Wales?

What type of court tomb is it? it looks like a terminal one (with only a central chamber), boffins used to believe this was the earliest type, but I'm not sure if this idea is still in favour.

Ty Isaf court tomb has a funky rotunda behind two (?) lateral chambers and a later smaller tomb added onto the back of the rotunda, so reworking is not out of the question.