Bwlch yr Eifl, near Trefor

Bwlch yr Eifl, near Trefor

Here the Wales Coast Path passes through Bwlch yr Eifl (Bwlch = pass). On the seaward side is one of the three peaks of Yr Eifl (often known in English as The Rivals). The highest is on the other side, and beyond it are the well-preserved remains of the Iron Age hillfort known as Tre’r Ceiri.

Yr Efil is the highest ground of the Llŷn Peninsula, rising to over 500 metres above the sea. It was formed by volcanic activity along the geological fault which underlies the peninsula’s north coast.

The hard rock was useful for construction. In the 19th century there were several quarries on Yr Eifl, including the extensive “Gwaith Mawr” near Trefor. They benefited from proximity to the sea, as ships were the most cost-effective way of moving large volumes of granite.

Photo of Iron Age brooch found at Tre'r Ceiri
Gold-plated brooch from Tre'r Ceiri
© Amgueddfa Cymru – National Museum Wales

Similar quarrying at Penmaenmawr, further east along the coast, completely destroyed an extensive hillfort but fortunately Tre’r Ceiri was left untouched. The main rampart encloses the foundations of c.150 circular huts. The rampart remains in such good shape that you can even see the walkway along the top, accessed via ramps. There are two clear entry points and three small postern gates, one of which was probably used by residents to fetch spring water.

A section of outer wall offered further protection where attack would have been easiest (from the west and north).

The fort was probably built towards the end of the Iron Age (c.800BC to 43AD) and remained in use until the 4th century (the date of Roman pottery found there) or later. Many other objects have been found by archaeologists there.

They include a gold-plated brooch (pictured) dating from the late 1st century AD to early 2nd century AD – the early Roman period. The gilded decoration on this brooch is of the late Celtic Art style (sometimes known as La Tène), suggesting that this style appealed to Iron Age communities living in the fort in the decades following the Roman invasion of western Britain. The brooch’s similarity to objects found in Ireland suggests contact between people each side of the sea.

With thanks to Gwynedd Archaeological Trust and Amgueddfa Cymru - National Museum Wales

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