In 1868, the parish of Merthyr Tydfil contained the following places:
"MERTHYR TYDFIL, a parish, market town, and parliamentary borough, in the hundred of Caerphilly, county Glamorgan, 17 miles from Brecon, and 20 from Abergavenny. It has stations on the Vale of Neath and Taff Vale railways. There are also several tram-roads from the ironworks, mines, and collieries in this rich mineral district to the basin of the Glamorganshire canal, which traverses the country from Merthyr-Tydfil to Cardiff, where it terminates in a floating harbour, opening into Penarth Roads. The town of Merthyr is situated near the northern boundary of Glamorganshire, at the head of the vale of Taff, celebrated for its rich and thick veins of coal, in juxtaposition with parallel veins of argillaceous iron ore, which penetrate the mountains to a great depth, and yield, upon an average, thirty-five parts of metal out of one hundred. Previous to 1755, it was an inconsiderable village, at which time the late Mr. Bacon obtained a lease of ninety-nine years from Lord Talbot, of Hensol, of the mineral ground, about 8 miles long by 4 broad, at the rate of £200 per annum. He erected a furnace at Cyfartha, and supplied the government with cannon until 1783, when he disposed of this mineral region in bases, having previously realised an immense property. Since this period it has gradually increased in population, numbering in 1851, 63,080, and in 1861, 83,844 inhabitants, including the neighbouring works of Penydarren, Cyfartha, and Dowlais, and the village of Coed-y-cumar, with the adjoining parish of Aberdare, which are included within the borough. Although the metropolis of the iron trade, and the producer of almost incalculable wealth, it was till within the last few years a dirty, neglected place, badly supplied with water and unpaved. As may be expected, the usual consequences of such a state of things manifested themselves in the high mortality as compared with the neighbouring towns, and in the frequent recurrence of fever, small pox, and cholera. Great improvements have, however, been recently made, and the streets are now paved and lighted with gas, and extensive waterworks are in course of construction. The town is situated 500 feet above the sea-level, and is drained by the river Taff, which flows through it. The central part is almost wholly composed of long rows of workmen's cottages, without architectural adornment of any kind, but on the S. side of the town a suburb of neat villa residences has sprung up. It has no public buildings of any interest, the only places worth mention being the theatre, banks, philosophical society, several book clubs, and three market-places. The members of the Temperance societies are very numerous, as are also the Odd Fellows, both of which fraternities frequently parade the streets in holiday attire. The life and trade of Merthyr are wholly absorbed in the numerous ironworks in the vicinity, which are the most extensive in any part of England, including the two vast concerns of Dowlais and Cyfartha, which are like townships in themselves, sprung solely from the iron manufactory under the spirited direction of Sir John Guest, Lewis, and Co., and the Messrs. Crawshay; the former establishment producing above 1,000 tons of iron bars, rails, and rods per week, employing upwards of 4,000 hands, and the latter about 900 tons of cast iron per week, the greater part of which is converted into malleable iron. Besides the Cyfartha, which are said to be the neatest and best arranged works in all South Wales, the Messrs. Crawshay possess the Hirwain Works, situated about 6 miles from Merthyr, The Pen-y-darren Iron Company also produced about 500 tons of malleable iron per week, but these works have been recently closed from pecuniary difficulties, a serious blow to the town and trade of Merthyr generally. The first locomotive steam-engine was constructed here in 1805, by Messrs. Vivian and Trevethick, who tried it on the Taff Vale line, or rather tramway, and the experiment was so far successful that the engine proceeded as far as Pontypridd, and there came to a stand. At a short distance from the town on the side of Mynydd Aberdare, stands Cyfartha Castle, the modern residence of Mr. Crawshay, and about three miles to the N., on the top of a mountain, are the ruins of the ancient Castle of Morlais, said to have been the seat of the King of Brecon, but dismantled by the parliamentary army in the reign of Charles I. The petty sessions for the upper division of the hundred of Caerphilly are held in the town, which is a polling-place for the county elections. By the late Act for amending the representation of the people, Merthyr-Tydfil was constituted a borough in conjunction with the adjoining parish of Aberdare and the village of Coed-y-cumar, in the parish of Vainor, with the privilege of returning one member to parliament. The borough is under the superintendence of a stipendiary police magistrate, appointed by Act of Parliament of the 10th of George IV. The cleaning and lighting of the streets are under the superintendence of a local board of health. It is also the head of new County Court and superintendent registry districts. The living is a rectory* in the dioc, of Llandaff, value £675. The church is a plain structure, with an inscribed slab in the outer wall, representing "Arthur," a brother of St. Tydfil, to whom it is dedicated. The new church of St. David is also a neat building, erected in 1846. There are also two district churches, viz: at Pont-y-Rhun and Cyfartha, the livings of which are perpetual curacies The various denominations of Protestant Dissenters have places of worship, and there is a Roman Catholic chapel. The state of education is advancing rapidly in this neighbourhood, and most of the young people can now read and write, which was not the case some twenty years ago. There are National, infant, and denominational schools, but the Sunday-schools are the most regularly attended, numbering above 6,000 scholars. Market days are Wednesday and Saturday. Fairs for cattle are held at Merthyr on the 14th May, and at a place called Twyny-Waun, in this parish, on the first Mondays in July and August."
"CYFARTHFA, a chapelry and village in the parish of Merthyr-Tydfil, in the county of Glamorgan, 2 miles from Merthyr-Tydvillage The living is a curacy in the diocese of Llandaff, value £130, in the patronage of the crown and the bishop alternately. Here are extensive iron and coal works, employing about 5,000 persons. Cyfarthfa Park is the seat of William Crawshay, Esq., the great ironmaster."
"CYNON, a hamlet in the parish of Merthyr-Tydfil, in the county of Glamorgan, near Merthyr-Tydvillage It is situated at the junction of the rivers Pynon and Taf, where the Cardiff canal crosses."
"DOWLAIS, a chapelry in the parish of Merthyr-Tydfil, in the county of Glamorgan, 2 miles N.E. of the town of Merthyr. The hamlets of Heol-wermood and Garth are included in this chapelry The extensive iron-works here afford employment to most of the inhabitants. The living is a rectory in the diocese of Llandaff, value £150, in the patronage of the Marquis of Bute. Dowlais House is the seat of Sir J. Guest, Bart., proprietor of the iron-works."
"FOREST, a hamlet in the parish of Merthyr Tydfil, county Glamorgan, South Wales, in the vicinity of Merthyr Tydvillage"
"GARTH, a hamlet in the parish of Merthyr-Tydfil, county Glamorgan, 2 miles N. of Merthyr-Tydfil. It is a rich mining district, and most of the inhabitants are employed in the ironworks and collieries. Cyfarthfa is the residence of William Crawshay, Esq."
"GELLI DEG, a hamlet in the parish of Merthyr-Tydfil, county Glamorgan, South Wales. It is situated on the river Taf, and abounds in coal, the working of which affords employment to the people."
"HEOL-WERMOOD, a hamlet in the parish of Merthyr-Tydfil, county Glamorgan, 2 miles from Merthyr-Tydfil. It is situated near the canal, in the midst of a mining district. The inhabitants are chiefly engaged in the iron-works."
"HIRWAIN, a hamlet in the parish of Merthyr-Tydfil, hundred of Caerphilly, county Glamorgan, 7 miles from Merthyr-Tydfil, and 22 N.W. of Cardiff. It is a station on the Vale of Neath railway."
"PANT, a hamlet in the chapelry of Dowlais, parish of Merthyr-Tydfil, county Glamorgan, 2 miles N.E. of Merthyr-Tydfil. It is a station on the Merthyr and Brecon railway."
"PEN-Y-DARREN, (or Pennydaron), a hamlet in the parish of Merthyr-Tydfil, hundred of Caerphilly, county Glamorgan, 2 miles from Merthyr-Tydfil. It is situated near the river Taff and Cardiff canal, and is celebrated for its extensive iron works, employing above 2,000 hands.
"PLYMOUTH, a hamlet in the parish of Merthyr Tydfil, hundred of Caerphilly, county Glamorgan, 2 miles from Merthyr, and 22 N. by W. of Cardiff. It is situated in the valley of the Taff, and has large coal and iron works."
"TAFF-WITH-CYNNON, a hamlet in the parish of Merthyr Tydfil, county Glamorgan, 6 miles S. of Merthyr Tydfil. It is situated on the Taff river, which rises under Brecknock Beacons, in South Brecon, in two heads, and flows 35 miles to the Bristol Channel, at Cardiff."