Moel Fenlli () is located within the Clwydian Range to the south of Moel Famau, above Bwlch Pen Barras on a prominent hill. It is first noted by the Tudor antiquarian William Camden[i] in 1607 in the text Britannia ‘For such is the wonderfull workmanship of nature that the tops of these mountaines resemble in fashion the battlements of walles. Among which the highest is Moilenlly, on the top whereof I saw a warlicke fense with trench and rampier, also a little fountaine of cleere water'.

It is a multivallate hillfort with extensive ramparts on the north and east but with slight defences to the south where the natural slope is extremely steep.

The ramparts enclose an area of 9.5 hectares. The site has one original inturned entrance way at the west. Just like Penycloddiau to the north the fort is not a true contour fort but dips from its highest point in the east at the entrance way on the west[ii]. There are also the remains of a possible Bronze Age burial mound inside the fort at the highest point of the hill.

It was following the discovery of a hoard of 1,500 Roman coins in 1816[iii], which came to light after an accidental heather burn, that W Wynne Ffoulkes began his programme of investigations on three Hillforts (Moel Fenlli, Moel y Gaer Llanbedr and Moel Arthur) in the Clwydian Range in 1849. All of which were in the ownership of Ruthin Castle Estate.  Wynne Ffoulkes describes ‘making incisions' in various parts of the fort, in the rampart to the north; the southern section of the rampart where a track enters the fort; and in several possible hut platforms. He describes digging ‘trench after trench' without success. ‘Perseverance, however, at length brought to light a piece of white pottery, the rim of some vessel...'.Work continued and soon they dug up a ‘remarkable knife and very good glazed Roman pottery, partaking the nature of samian ware'. Artefacts found were in the collection of Ruthin Castle until the mid 1920s when Sir Mortimer Wheeler saw them[iv] but it appears that they have since been lost.

Both Ellis Davies[v], in the 1920s, and Forde Johnston[vi], in the 1960s, describe the site in detail and about two dozen hut platforms are noted as well as a dried up spring and possible water dam. Forde Johnston suggests two main structural phases to the development of the site. The first phase sees the construction of a complete circuit of bank, ditch and counterscarp bank[vii].

Some exploratory excavation work took place by Bevan Evans prior to a visit by the Cambrians in the 1950s[viii]. Information on granting of permission to excavate has been located in the Hawarden Record Office[ix] although the results of the work have not yet been located.

A  topographical survey was carried out in 2006 by EAS which identified 61 possible hut platforms.

[i] W. Camden 1607 Britannia - Philemon Holland's English Translation of 1610

[ii] Forde Johnston ibid

[iii] 1847 Archaeologica Cambrenis p108-11

[iv] Archaeology of Wales Mortimer Wheeler 1925

[v] Canon Ellis Davies 1929 Prehistoric and Roman Remains of Denbighshire

[vi] Forde Johnston ibid

[vii] Forde Johnston ibid

[viii] note in arch camb/Flintshire hist soc and Hawarden Record Office

[ix] Hawarden Record Office Bevan Evans Collection