[1] It dates from the Bronze Age (c. 3000–4000 years ago) and is the largest of the over 80 stone rows in south-west Ireland.

[2] The four Castlenalacht stones are arranged in ascending order of height across a distance of 13.4 m (44 ft).

[2][3] The site is placed on one of the area's highest hilltops; according to the archaeologist Clive Ruggles, the builders tended to favour locations where the axis, from largest to smallest stone, leads to a relatively distant (usually more than 5.0 km (3.1 mi) away) horizon.

[8] The precise functions of these constructions are unknown; most archaeologists assume a ceremonial or ritualistic purpose.

[7] A nearby field contains a large and near contemporary boulder-burial stone, known as the "Garranes Boulder burial", which is supported by three smaller stones measuring from 40 cm (16 in) to 60 cm (24 in) in height.