HAVODDRYINOG (HAVOD-DREINIOG), a hamlet, in the parish of LLANWONNO, hundred of MISKIN, county of GLAMORGAN, SOUTH WALES, 11 miles (S.) from Merthyr-Tydvil, containing 679 inhabitants. Near the junction of the Taf and the Rhondda, at the southeastern extremity of the hamlet, stands the modern and thriving village of Newbridge, where a weekly market for provisions is held, and whence a considerable quantity of corn is conveyed by the canal, for the supply of Merthyr-Tydvil. Within a quarter of a mile of the village is the celebrated bridge of Pont y Prydd, thrown from the bold and wooded banks of the DI across that river, consisting of one arch of one hundred and forty feet in the span and thirty-five in height, with three cylindrical and graduated holes in each spandril, to lighten the weight of the haunches, and a low para. pet on the top, so as to give the whole the extremely light appearance of an elevated bow projecting from bank to bank. This extraordinary effort of art was projected by, and executed under the superintendence of, William Edwards, son of a farmer in the neighbouring parish of Eglwysilan, who, after two unsuccessful attempts, accomplished his arduous undertaking in 1755. The view of the scenery up the vale of the Rhondda from the top of this bridge, and from another crossing that river at right angles with the former, is highly interesting and beautiful. There is a succession of three waterfalls within a short distance of each other, rivalling in grandeur and picturesque beauty: the first is called the "Salmon Leap," and the others follow between this and the junction of the Rhondda Vechan, where there is another bridge, called Pont y Cymmer, which, with the high, precipitous, and well-wooded rocks bounding these rivers, adds to the extreme beauty of the scene. A rail-road passes from the Cardiff canal up the right bank of the Rhondda Vawr to some coal-pits in the upper part of the vale.