Dinas Dinlle Dig Diary

Day 1

Dinas Dinlle Prehistoric Coastal Hillfort


And we’re off! We’re delighted to be back at Dinas Dinlle prehistoric coastal hillfort.

It’s been fantastic welcoming our volunteers on to site today! It’s the first time we’ve seen them in months!

The programme of excavation is being undertaken by GAT with grant aid by Cadw, the National Trust, the CHERISH project and AONB Llŷn. The excavation will be run as a community excavation with supervision from GAT staff.

The fieldwork will be undertaken by GAT staff and volunteers with additional input from Bangor University and CHERISH staff. Local schools and the Bangor branch of the Young Archaeologists’ Club will also be taking part.


Hello to our volunteers!

Day 2

Here's a short video clip from trench 1.



There will be two trenches excavated within the fort. In trench 1 we hope to fully excavate the roundhouse partially uncovered during the CHERISH funded 2019 evaluation excavation.

We will also further investigate the features revealed in trench 2 of the 2019 excavation - namely a possible roundhouse or terrace and smaller features that were buried beneath the post abandonment soil horizon.

Day 3

Here's another video clip - let's have a closer look at some of that delicious inner facing (roundhouse, trench 1):



We're slowly beginning to reveal this amazing roundhouse. The excitement is definitely mounting!

It's a huge roundhouse, the external diameter is some 13.5 metres, and in places the walls are 2.5 metres thick!

Here's a little more background information on the site...

Dinas Dinlle hillfort overlooks the sea from its perch on an isolated hill of glacial drift in the Caernarfonshire coastal plain. The fort, thought to be of late prehistoric origin, would have originally been defended by two earth ramparts with a deep ditch in between. Severe erosion has removed all traces on the seaward side but the defences are still visible from the south, east and north.

Day 4

We were blessed with beautiful weather today!

We're continuing to excavate and record the roundhouse in trench 1.

Roundhouse, Trench1

Inner facing, Roundhouse, Trench 1


In trench 2 we're hoping to fully identify the structure which was partially uncovered last time.

Trench 2


A member of the CHERISH team will be in attendance each week, assisting with the project. It's a joy too work with them again, the 2019 excavation seems like such a long time ago! Their expert input will be invaluable in shaping the outcomes of the project.

This week we've got none other than Dr Toby Driver!

Dr Toby Driver!

Day 5

Beautiful weather on site today!

Say hello to this week's group of volunteers (video, below):



Trench 1 and trench 2 (video, below):


Day 6

What better way to spend the morning than experiencing and recording one of Gwynedd's most iconic hillforts – Dinas Dinlle - from the air!

Dinas Dinlle hillfort from the air

Camera facing East


We were lucky enough to be able to join the CHERISH project's Toby Driver in a Robinson R22 helicopter, taking off from Caernarfon airfield earlier today.

We were able to capture footage and pictures of the exaction work at Dinas Dinlle hillfort (where we're working in partnership with the Cadw, The National Trust, the CHERISH project and AONB Llŷn).


Roundhouse, trench 1

Trenches 1 and 2


Day 7

Today we're clearing the tumble (stones which have fallen from the roundhouse walls) away from the sides of the roundhouse walls and recording the interior of the roundhouse using quadrants.

Roundhouse, trench 1


Roundhouse Interior


Also, we have an open day on Saturday 4th September. 10am - 4pm, come and find out about this year's excavations. Free, no booking required.

Park in the beach car park, meet behind the playground, next to the fish and chip shop, where the footpath starts to ascend the hillfort.

Social distancing please. Don't attend if you are experiencing any Covid-19 symptoms.



Day 8

Let's have a closer look at our roundhouse!


Trench 1 - we're excavating the huge roundhouse partially uncovered in our 2019 CHERISH funded evaluation excavation.

Day 9

Young Archaeologists' Club (YAC) session.


It's an amazing moment when a child or young person finds an important artefact!


That's what happened today - look at that amazing flint core, found in the roundhouse interior in trench 1.


We love it when that happens.

YAC Bangor branch:


Day 10

Geophysical survey - we use this technique to create a map of subsurface archaeological features:

An example of archaeological investigation which is non-invasive, helping us build up a picture of what’s going on under the ground without actually having to excavate.

Dave Hopewell, one of GAT’s senior archaeologists and site director, conducting a geophysical survey at the nearby Craig y Dinas hillfort.


GAT’s geophysical surveys at Dinas Dinlle helped determine the location of the 2019 evaluation excavation trenches. This time we’re concentrating on the fort interior, fully excavating the features partially uncovered during 2019 excavations.

2019 trench locations, (hillfort interior) and gradiometer interpretive plot


Here too are some pictures from the site today:


Day 11

As if one hillfort wasn’t enough! We’ve also despatched a team to carry out investigative work at the nearby Craig y Dinas hillfort. With support from Llŷn AONB.

Here is an image and some aerial footage of the site, taken last week:

More information on Archwilio:

Craig y Dinas Hillfort

Please note: Craig y Dinas is on privately owned land.


Day 12

Here are some of our wonderful volunteers hard at work today. We were blessed with beautiful weather today!

Come along to our open day, Saturday September 4th. 10.00am – 4.00pm. Enjoy guided tours of the site and find out about this year's excavations. Free, no booking required. Park at Dinas Dinlle beach car park and make your way towards the hillfort. Social distancing required. Dress according to the weather!


Day 13

The CHERISH team are using a drone to help photograph the site from the air. CHERISH have been in attendance each week, assisting with the project.

CHERISH Project:

Image © Crown CHERISH Project 2021


Image © Crown CHERISH Project 2021


Image © Crown CHERISH Project 2021


Daniel Hunt, CHERISH project


Day 14

Here are some pictures from our open day today.

Thanks to everyone who came along, and thanks to everyone who helped out today.


Day 15

This week is schools' week! We're delighted to be working with over 70 primary and secondary school children from the area. Our schools' programme involves class pre-visits where we contextualise the site within the wider landscape, discuss what it is to be an archaeologist before explaining to pupils how they will help Gwynedd Archaeological Trust with our work on site. Then pupils visit us at the hillfort, and, after a tour of the site, assist us with our recording work. Later in the week we provide a re-cap session for each class, back at school.

Today it was Ysgol Felinwnda's turn to visit us onsite.


Day 16

Schools’ week. Today it was Ysgol Llandwrog’s turn to visit us onsite. Once again we were blessed with gorgeous weather today!


Day 17

Here's some more of the Dinas Dinlle hillfort aerial photography we took recently.

We were offered the chance to view the site from the air via helicopter, accompanying the CHERISH project's Toby Driver.

You can see some our volunteers and staff in some of the shots.


Day 18

The weather wasn't quite as fantastic today. Nevertheless we are getting on with our work. The hillfort is in an exposed location, so if the weather is good it's spectacular, if the weather's not so good we feel the brunt of the wind and rain. It can mean you'll need sun cream and a raincoat on the same day!

Today and yesterday it was Ysgol Dyffryn Nantlle sixth form's turn to visit us onsite.

The Bangor Walking group made an appearance too.


Day 19

Our final (volunteering / schools) day at Dinas Dinlle prehistoric hillfort.

It's been a fantastic few weeks working with members of public again, helping us uncover more of the secrets at this, one of Gwynedd's most iconic archaeological sites.

Thanks to all our staff, Rhys Mwyn, our amazing volunteers and Bangor University students, all the school pupils who helped us with our work, our members of the Bangor branch of the Young Archaeologists' Club, Cadw, the National Trust, the CHERISH team, Llŷn Area Of Outstanding Natural Beauty, the BBC and to all the members of the public who have shown an interest in our work here.

Thanks too to the tenant farmer (Dinas Dinlle hillfort) and landowner (Craig y Dinas hillfort).





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