In 1868, the parish of Llangiwg contained the following places:
"LLANGIWG, (or Llanguick), a parish in the hundred of Llangyfelach, county Glamorgan, 6 miles N.W. of Neath, its post town, and 8 N.E. of Swansea. It is situated on the river Tawe, and the Swansea canal passes through it. The parish includes the hamlets of Alltgreig, Blaenegel, Caegurwain, and Mawr. Here are collieries and ironstone mines, and also anthracite and culm are obtained. It is a large and thriving village. The living is a perpetual curacy in the diocese of St. David's, value £103. The church is dedicated to St. Ciwg.
"ALLTGREIG, a hamlet in the parish of Llangiwg, hundred of Llangafelash, in the county of Glamorgan, South Wales, 5 miles to the N.W. of Neath."
"CAE-GURWAIN, a hamlet in the parish of Llangiwg, hundred of Llangyfelach, in the county of Glamorgan, South Wales, 9 miles to the N. of Neath. It is seated in a rugged district on the border of Carmarthenshire, on the small river Twrch."
"MAWR, a hamlet in the parish of Llangiwg, hundred of Llangyfelach, county Glamorgan, 5 miles N.W. of Neath."