Three features at Twyn y Post have been recorded and described as probable Bronze Age funerary or ritual monuments, the group being given Scheduled Ancient Monument status by Cadw in 1993. A variety of terms have been applied to describe the group and its individual features, creating some confusion when the records of Cadw, the RCAHMW and the regional archaeological trust are compared.

The features at Twyn y Post have long been the subject of antiquarian interest, with Theophilus Jones being the first person to describe them, in ?A History of Brecknock?, published in 1809. Jones referred to the site by its earlier name of Pen y Pebyll, which undoubtedly corresponds with the name Post y Pabell, given to this location on the 1831 Ordnance Survey map. The 1891 Ordnance Survey map gives the name Post y Pebyll. The name Twyn y Post does not appear on Ordnance Survey mapping until the 2nd edition Ordnance Survey maps of 1904.

The RCAHMWs Brecknock Inventory mistakes Jones? description of Pen y Pebyll for a stone circle at Ynys Hir, elsewhere on Mynydd Epynt. In reality, Jones? provides an excellent description of features at Twyn y Post, however;

?On the Epynt Hills, at a place called Pen y Pebyll, or the summit of tents (I believe within the parish of Merthyr) are two circles similar to the Senor circles, described by Borlase?; the largest is about 50 paces in diameter, the loose surrounding agger of stones about 7 or 8 feet in thickness, with an entrance on the east; the smaller about 14 paces in diameter and near it a carn or raised heap of stones.?

This description firstly identifies the circular enclosure of Cornelau Uchaf (NPRN 305776), near Twyn y Post, and then mentions a second circle at Twyn y Post itself, with which is associated, importantly, a single cairn. It seems likely that this second circle is the earthwork monument on Twyn y Post NPRN 247190, which has been described as a ?hengiform? monument (Ordnance Survey 1980 & CPAT PRN 4066) and a ring cairn (RCAHMW Brecknock Inventory site no. RC236). Although the true nature of this monument remains uncertain (see NMR description for NPRN 247190), it is interesting to note that it was considered to be a circle of antiquarian interest in the early 19th century.

Jones? reference to a single cairn alongside the Twyn y Post circle is at odds with recent records (e.g. the regional HER and the RCAHMWs Brecknock Inventory and NMR database), as well as the 1831 Ordnance Survey map, which record three monuments at Twyn y Post and have led to the site being described as a Prehistoric Monument Complex. The three features are the earthwork NPRN 247190 to the south and the stone cairn NPRN 247188 to the north, between which is a postulated third monument (NPRN 247189), described variously as a cairn (CPAT), a ring cairn (RCAHMW Brecknock Inventory) and a stone spread (Trysor, 2009, Uplands Initiative Banc y Celyn survey). It is worth noting that this rather ephemeral feature corresponds with the position of a triangulation point shown on the 1st and 2nd edition 1:2500 Ordnance Survey maps of 1888 and 1904. The erection and removal of the triangulation point may have either damaged an existing cairn, or created the present stone spread in this area. However, the depiction of three monuments on the 1831 Ordnance Survey map does seem to suggest that the former is the more likely explanation. It is not impossible that Theophilus Jones described the adjacent stone cairns NPRNs 247188 & 247189 as a single cairn.

There is little doubt that the third feature in the group is indeed a Bronze Age funerary cairn (NPRN 247188). Its stony mound is partly obscured by reeds and grass, but can be seen to be largely intact and measure at least 11m in diameter and stand up to 0.4m high, with the stones of a cist possibly standing at the northwestern end of the mound.

The variation in character between these three monuments is considerable and questions should be raised as to whether they are indeed contemporary or share a common function as funerary or ritual monuments.

Their position at a crossroads of important tracks across the Epynt common is interesting, as they have undoubtedly provided important landmarks for many centuries. The original name of the site, Pen y Pebyll, the ?Summit of Tents? raises questions about possible transient settlement or other activity at this point. The later names, Post y Pabell and Twyn y Post, may suggest that a post of some form might have been raised here at some point, potentially after Theophilus Jones? visit in the early 19th century, which could imply some disturbance of features on the hill.

J.J. Hall, Trysor, 2009