Rather than

From sweet Londonderry to the fair London town,
There is not a nicer harbor, anywhere to be found,

could it be that Triona Ni Dhomhnaill sang

From sweet Londonderry to the fair London town,
There is not the likes of her there, anywhere to be found

It's what my ears hear at any rate and seems to make more sense than a lyric worthy of a clerk of works!