Thanks for those links, Malcolm. My rudimentary Welsh tells me that the first verse mentions many other places in the vicinity of Llangollen, but not what it says about them.

The morris tune consists of two 8-bar sections, and the dance is ABA repeated 6 times. Both the Welsh and the broadside versions would fit very well if the tune were played AABA.

Interesting that your first link gives yet another variant of the second line ("the girl I love best") - I've just checked in Lionel Bacon's "A Handbook of Morris Dances", (The Morris Ring 1974), and he gives those words too. It appears the folk process is alive and well among morris dancers - well a song of two whole lines is bit too much for us to get completely correct, I suppose.

Does anyone know any more of the song which accompanies the morris dance?