Treforys Dig Diary



Treforys – further information:

Day 1
18th February 2021

Reasonable weather meant that we could spend the day up at Treforys recording the crog loft cottages at the abandoned quarrymen's settlement serving the nearby Gorseddau Quarry. Built in 1857 many of the cottages are now in a poor state of preservation (36 in total). Cottages No 12 and 13 (in the middle row) were recorded today with suggestions as to how the buildings may be preserved or consolidated and what conservation measures may be needed.


Day 2
22nd February 2021

Blocked window, cottage 13

We have noticed large windows on the front elevation of cottages 12 and 13. This may have been the 'fashion of the day' with an emphasis on getting 'light' into the rooms. The windows however appear to have been blocked up reducing the window space by almost 50%.

Is it possible that the architect was not familiar with the harsh weather up at Cwm Ystradllyn? This is something we are asking at the moment. (There may be a similar story in the cottages up at Cwm Orthin).

Neil and Rob busy getting the recording process underway


Day 3
25th February 2021


It seems increasingly apparent that the cottages at Treforys follow a common plan. There may be slight variations due to topography but even when examining the most dilapidated cottage it is possible to make out the central partition forming the pair of dwellings. Each cottage has a further internal division. The front doorways are on the south facing elevation and there seems to be no doorways onto the roads – they are always to the north of the buildings. Very few outbuildings have been found which raises an interesting question about 'toilet' facilities. Possibly a bucket and disposal in the streams?


View from top of site


Day 4
5th March 2021

We were blessed with good weather today and it was possible to fly the drone. Four of the buildings were recorded by drone for 3D modelling.

Meanwhile work continues recording the buildings on the lower and central rows. The recording process involves taking measurements, compiling a photographic record and noting recommendations for future conservation work. We have now devised a grading system from 1 to 5, 5 being for structures in need of the most urgent conservation work and 1 applying to a collapsed building which is now more or less in a stable condition.

Central row

Gable end, cottage 13


Day 5
8th March 2021

Monday 8th March was a good clear day with low wind and we were able to record four of the buildings in the central row at Treforys with the drone. These images will be used to create 3D models of the buildings.

Building recording of the lower (southern) row of houses continues as does the recording of the central row.

One important breakthrough to understanding the drainage system at Treforys was the discovery of one of the underground culverts which would have directed water away from the houses. We now need to find a way of photographing the culvert.

Neil operating the drone

Rob, lower row


Day 6
13th March 2021

Cottage 13, internal partitioning of second room

Wide doorway, cottage 13

Several questions were answered as a result of being given access to drawings of Treforys in 1974 from a survey undertaken by Hull University. The drawings of the houses show a further downstairs partitioning suggesting a main room next to the fireplace and a side room sub-divided against the gable end. The evidence for subdivision of the side room can be seen by small holes for a wooden partition running up the middle of the gable end of cottage 13 to crog-loft level.

A clue is also given by the wide doorway in cottage 13 (the only example surviving in the middle row) which looks like it would have had two doors – one each side of the partition frame. Could these subdivisions suggest a downstairs bedroom and possibly a parlour?



Day 7
15th March 2021


Drainage channel running down from centre row

When Treforys was constructed in 1857 an extensive drainage system was designed to drain the site and keep the water that naturally runs down from Moel Hebog away from the village. Some of the drainage channels may also have been used to remove sewage. One of the aims of the current recording project at Treforys is to map out this drainage system. Some of the leats are obviously visible on the ground but other water channels run in underground culverts.

One of the culverts was discovered and with great difficulty a mobile phone was held underground in an attempt to get a working shot.


Day 8
17th March 2021

Our condition survey at Treforys continues. To re-cap - the recording process for each cottage involves the compilation of drawn and written records, a photographic record and photogrammetric modelling (using images captured by drone). There are 18 cottages, each divided into two separate dwellings, spread across three rows:

Here's Rob, compiling his photo record of cottage 6, in the top row. Firstly, a series of general photographs are taken of the exterior of the building:

A corresponding entry is added to the written photographic record, including a compass bearing indicating which direction the photograph was taken from. Rob then moved on to photograph more specific features of the building. A particularly nice feature of cottage 6(A) is the fireplace in the south-west wall:

The lintel is deceptively thin and precariously balanced:

Recording work continues at the other two rows. A 3D photogrammetric model of each cottage will be created, using images captured by drone. In total, some 4000 drone images will be used for this project. Here's the drone in action above cottage 13, the best preserved of all the cottages:

And here's Rhys recording cottage 14.

Day 9
19th March 2021

Cottage 2 on the upper row at Treforys is unusual because it has a stream flowing right through the living room of 2B. Much of the site is very wet underfoot and it's quite obvious that the drainage system of leats and culverts has seen better days since abandonment in the 1870s.

But this is something else, a natural stream has found a new course right through the building. Nature always wins.


Day 10 and 11
22nd and 24th March 2021

Outbuilding between cottages 1 and 2

Outbuildings are noticeable by their absence up at Treforys. The lower and central rows certainly have no suggestion of any coal sheds, pigstyes or ‘tai-bach’ / toilet buildings.

However, on the upper row between cottage 1 and 2 there is a cell like structure just over a meter in width with a curving wall forming an annexe beyond the structure. It lies on the same orientation as the cottages – broadly south-west by north-east.

About 50m to the south is another square structure, approximately 2m square in dimension of unknown function.

Day 10 and 11 have been spent recording these structures along with much discussion about their possible function.

Unknown square structure at Treforys

Unknown square structure at Treforys showing wall facing

Final Day
30th March 2021

30th March was our final day on site. Neil has completed the drone survey which has produced some stunning aerial shots of Treforys:

We walked along the drainage system of culverts and leats that were constructed for Treforys and have completed an initial survey including photographs, field notes and sketches on maps that provide a greater understanding of the archaeology on the ground.

The results of the condition survey will be used to inform future preservation work.



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