The River Thaw which meets the sea at Aberthaw is fairly small and is affected by high tides at times, and with the coming of the first coal-fired power station at Aberthaw circa 1958, was diverted to form a straight channel about 959 yards long from the fixed coastline and this section is therefore within the Power Generation Board's property.

[5] There were settlements in the second and third centuries, substantiated by Roman pottery, shells and tiles that were discovered when a new pipeline was laid through East Aberthaw in the 1950s.

[8][9] The village, which came within the parish of Penmark,[10] is also known to have included a small chapel which was possibly located towards the south of the settlement, as suggested by the marking of 'Chapplefeld' on the Evans Mouse map of 1622.

[11] The ships took wool and foodstuffs from Wales and returned with wine, salt, dried fruit and leather from the towns of northern France.

A similarly flourishing trade with the West Indies, chiefly in sugar and tobacco, did not, however, survive the disruption caused by the outbreak of the English Civil War.

Within the context of the village, the port played a significant role in the livelihoods of many residents in the 17th century, though not always in a legal manner: smuggling was rife within the Bristol Channel.

Buildings such as the fortified Marsh House, built just to the west of the village in 1636, appear to have been used for storage of illegally imported goods, especially tobacco.

Aberthaw's maritime trade continued throughout the 18th century, but by the 1840s, its role as a port declined: the harbour 'is resorted to by a few coasting-vessels of inferior burthen', as the Topographical Dictionary of Wales in 1849 reported.

[16] The principal material then being exported, however, was the local lias limestone, called Aberthaw tarras, which was used to make hydraulic lime, which sets under water and was therefore very useful for building light houses (including the Eddystone Lighthouse) and canal locks.

This limestone, considered to be of high quality,[17] was to play a key role in the local economy during the ensuing years, beginning with the opening of Aberthaw Lime Works in January 1888.

[18] From December 1897, the area was served by the newly constructed Vale of Glamorgan Railway,[19] and a second plant, the Aberthaw and Bristol Channel Portland Cement Works, began production to the north of the village in 1916.

The establishment of these industries close to Aberthaw was to result in an increased demand for residential accommodation, and by 1919, two new communities had been added at the northern and southern edges of the village.

The community, by this time, had gained a Methodist Chapel and a Mission Room,[21] the latter erected in an Arts and Crafts style on Station Road.

[26] Close by is the Grade II listed Marsh House, an 18th-century building with a symmetrical front and a slated catslide roof.

[citation needed] The latter, which also served the now Grade II-listed Aberthaw (Pebble) Lime works from 1892 until 1926 and ran from Llantrisant via Cowbridge, was lifted by June 1934.

Aberthaw signal box, being the only remaining example of its kind, is now devoid of all internal equipment and is a Grade II listed structure, but inaccessible to the public.

To the east from the crossroads, Port Road, a narrow lane, leads uphill to a farm group (Upper House Farm) and then passes over Aberthaw Cement Work's tunnel-connected extensive blue lias limestone quarries and on to some woodland at the hamlet of Fonmon, with alternative unclassified road access to Fontygary and Rhoose or to the B4265, passing Fonmon Castle.