About one mile from Llyn Ogwen, in a deep hollow of the Glyder mountains, lies the dark pool, called Llyn Idwal. The gloomy horrors of the surrounding scene exceed even those of Ogwen; the encircling cliffs are overhanging, broken, and dark; in one part the whole mountain is rent asunder, and the chasm of “Twll ddû,” or the “black cleft,” gapes between the terrific masses. The solitude of Cwm Idwal proved favourable to the perpetration of a deed of blood, and it was here that young Idwal, the infant heir of Prince Owen Gwynedd, was treacherously assassinated by order of his foster-father Nefydd, to whose care his father had consigned him:— And thou, O Idwal, of immortal fame, Dying, to the vale hath left thy name. PONT-Y-PAIR {50a}. THIS curious and picturesque bridge is thrown over the rapid river Llugwy, {50b} at the village of Bettws-y-Coed, {50c} in the county of Caernarvon. Though flung high above the surface of the water it consists of but little masonry, the natural rock supplying piers the most solid and enduring. One of the arches affords an open transit for the waters which flow from the noble fall and salmon leap above the bridge, and produce by their impetuous rotatory motion a deep reservoir or caldron below it, whence this graceful structure derives its appropriate name. Four of the arches are dry except in rainy seasons, when the torrent rises with such rapidity as would endanger a less substantial work, at which period these openings are found perfectly necessary. The history of the origin of Pont-y-Pair possesses a singular though simple interest. Howel, a mason, from Penllyn, having occasion to attend the assizes then, A.D. 1468, held at Conway, found his passage over the Lleder, which flows through Dolwydellan, obstructed by the violence and greatness of the flood. This suggested to him the idea of removing to the spot and of erecting a bridge there, at his own expense, trusting to the generosity of travellers for compensation. The success of one project engendered a second, and Howel next resolved upon the erection of the beautiful bridge at Bettws-y Coed, called now the Pont-y-Pair; but he did not live to see its final completion.