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A final dig at the site of an early medieval chapel on a Pembrokeshire Coast National Park beach is expected to reveal more about people living in Wales 1,000 years ago.

Archaeologists have already carried out two excavations at the site of St Patrick’s Chapel in the dunes at Whitesands Bay, St Davids.

Almost 50 skeletons dating to the 7th and 11th centuries have been uncovered. Many were in ‘cist’ graves – long graves lined with stone slabs. Child graves were also found decorated with layers of quartz pebbles and limpet shells.

Now Dyfed Archaeological Trust will be excavating again and will conduct free tours every day from May 9 to 27. National park rangers and voluntary wardens will help to prepare the site by removing turf and sand.

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Bones reveal information on 7th century diets

Ken Murphy, of Dyfed Archaeological Trust, said bone preservation in the first two digs had been very good and that a significant find was a stone cross standing at the end of one of the graves – the first time in Britain that an upright stone cross had been found in association with a long cist grave.

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“Bone analysis by the University of Sheffield will provide information on the diet of the people who are buried at St Patrick’s Chapel and even on where they were born. The results of the excavation will greatly advance our knowledge of the lives and the beliefs of the people who lived in Wales over 1,000 years ago,” he added.

The excavations are funded by Cadw (Welsh Government), the Nineveh Charitable Trust, and the University of Sheffield and supported by Pembrokeshire Coast National Park Authority.

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Remains exposed by storms

The chapel, from where St Patrick is said to have set sail for Ireland in the fifth century AD, was a ruin more than 400 years ago but its location has never been forgotten and graves with human remains have regularly been exposed by storms.

Phil Bennett, the National Park Authority’s culture and heritage manager, said: “We placed boulders against the site of the chapel to halt erosion 12 years ago but they were washed away in the winter storms of 2014, exposing more burials. So we then decided to excavate the parts of the site most vulnerable to erosion and the aim of these digs is to ensure no more archaeology will be at risk for the next 50 years.”

The daily dig tours are free and no booking is necessary. The chapel site lies 50m from the car park at Whitesands Bay.

On the weekends of May 14-15 and 21-22 there will be longer guided tours to include a visit to the archaeological remains on nearby St David’s Head. To join one of these tours contact Sarah Rees on 01558 825999 or s.rees@dyfedarchaeology.org.uk.