Penydarren Roman Fort

Auxiliary Fort

The Roman fort at Pen-y-Darren or Penydarren is located on a spur overlooking the Afon Taf just south-west of Penydarren House (built 1786, now demolished), but nothing is now visible, the site being occupied by a football stadium built in 1902-5.

The first evidence for Roman occupation in Merthyr Tydfil was noted in 1786 during the construction of Penydarren House for the Iron Master Samuel Homfrey when both Roman bricks and tessellated pavement (mosaic) were revealed.

Later, between 1902 and 1904 during the preparatory groundworks for construction of the Merthyr Tydfil Athletics Club track and later football ground, the remains of a Roman granary, a building with a hypocaust system (Roman central heating) and a water-well were discovered. This was the first time that the site was considered to be that of a Roman fort, following the examination of the site by Dr F Haverfield of Oxford University.

Rescue excavations were later undertaken in 1957 by Dr Brenda Heywood from the University of Cardiff, supported by university students and pupils from a local school. The eastern corner-angle was positively located during excavations conducted by Heywood in 1957, although most of the dating evidence was accumulated in rescue excavations by Treharne-James during construction of the stadium.

The defences uncovered in 1957 consisted of a turf and clay rampart about 27 feet (c.8.2 m) wide, set upon a cobble foundation and separated by a narrow berm only 2 feet (c.0.6 m) wide from its ditch system which was double, the inner ditch about 13 feet (c.4 m) wide and the outer ditch 10 feet (c.3 m) wide, were separated by a berm of about 8 feet (c.2.5 m). A large post-hole presumed to have been part of a timber corner-tower was also recorded.

In addition, a small section of possible via sagularis (the perimeter road running behind the rampart on the inside) was found within the east rampart and the remains and traces of two ovens in the intervallum (the area found between perimeter road and rampart). From the excavation and its results, it has been postulated that the fort undertook a second phase of building and was occupied until c AD 140.

What did the Penydarren Roman Fort look like?

The actual plan and dimensions of the fort are not known, but if the well recorded by Treharne-James in 1905 was centrally placed within the principia and a square outline is assumed, then the dimensions would have been in the region of about 500 feet (c.152 m) square across the rampart crests, and would have covered an area of almost 5¾ acres (c.2.3 ha).

The dateable material is almost all early and clearly indicates that the fort was founded by Frontinus in the period 74-78. It does not appear to have been held for very long. Recent re-examination of the pottery evidence indicates that occupation continued during the first third of the second century but no later.” (RCAHMW)

Flavian pottery recovered from the site attests an early foundation for the original timber fort, very likely during the governorship of Sextus Julius Frontinus , which was replaced in stone around the turn of the second century. The bath-house outside the fort’s southern defences is probably contemporary with the rebuilding of the fort itself, but the latest pottery recovered from the site is Trajanic, which suggests that the site may have been abandoned in the Hadrianic period and its garrison removed to man the northern defences of the province.

References for Pen Y Darren

  • An Inventory of the Ancient Monuments in Glamorgan by the RCAHMW (HMSO, Cardiff) vol.1, part ii, pp.84-6 & fig.48;
  • Britons and the Roman Army by Dr. Grace Simpson (Gregg, London, 1964).

Roman Roads near Pen Y Darren

SE (8) to Gelligaer (Mid Glamorgan)

Location of Pen Y Darren

OS National Grid Reference: SO050067
Dimensions: c.500 x 500 ft? (c.152 x 152 m?)
Area: c.5¾ acres? (c.2.3 ha?)


Sites near Penydarren Roman Fort