Uaman, sídh of, [141].

Uaran Garad, spring of, [165].

Uffern, the “Cold Place”, a name for Annwn, [319].

Uisnech, the hill of, [69], [324].

Ulster, [29], [57], [64], [69], [76], [158], [164], [165], [166], [171], [174], [175], [180], [183], [188], [189], [190], [191], [192], [217], [245].

“Undry”, the name of the Dagda’s cauldron, [54], [366].

Unius, the river, [107].

Unsenn, the river, [112].

Urddawl Ben, see Venerable Head.

Urien, an Under World king, [328], [329], [357], [376];