Photo: nantcoly · CC BY-SA 2.0Old homes in Treharris: 47% built before 1919
For Treharris, that is 3 times the typical town’s share, 15%. Cadw lists 2 buildings inside Treharris’s built-up area, 4 for every 10,000 residents. Treharris grades C for history: #20 of 32 in Mid Glamorgan.
Where Treharris’s history is
Every Grade I and II* building, monument and historic park.
Hover a dot for its name; tap one with a photo to open it.
Cadw lists buildings of special architectural or historic interest in three grades: Grade I for buildings of exceptional interest, Grade II* for particularly important buildings of more than special interest, and Grade II for buildings of special interest. Listing protects the whole building, inside and out.
Every entry on Cadw’s register of listed buildings whose point lies inside the ONS 2022 built-up-area boundary. One list entry can cover a terrace or a group of buildings.
2 Grade II listed buildings
Most listed buildings are in this grade, which covers buildings of special interest. Open any building to read its official list entry.
All 2 Grade II listed buildings, A to Z
1 conservation area covers 12% of Treharris
Areas the council protects as a whole: demolition and changes to how buildings look need consent, and trees are protected.
2 of the 2 listed buildings stand in one.
Cadw’s conservation areas via DataMapWales. Hectares are the part of each area inside the built-up area.
Treharris grades C for history
Protected heritage and the age of the town’s homes, against all UK towns.
Two measures, each ranked against every UK town of 1,000 or more, with protected heritage counting twice as much as the age of homes. Protected heritage counts each listed building by its grade (Grade I three points, II* two, II one), each scheduled monument and battlefield two, and each registered park or garden by its grade; it is ranked both per 10,000 residents and as a total, so a village with one fine church doesn’t outrank a historic city. The second measure is the share of homes built before 1919, from the Valuation Office Agency’s council tax records. History is a character grade: it describes the town and isn’t part of the overall grade.
47% of Treharris’s homes were built before 1919
Every home by when it was built, from council tax records, against England & Wales (the dark tick).
44% of homes are Victorian or older, against 16% across England and Wales. The busiest period since was 1983–92, which added 14% of today’s homes.
Valuation Office Agency, council tax stock of properties by build period, 31 March 2025, for the neighbourhoods (LSOAs) that make up the town, split by where their residents live. Homes with no recorded build period (0 here) are left out; 1939–44 is not a period in the data.
Listed buildings in the places around Treharris
Treharris in brief
Old houses are part of Treharris’s character: 47% of its homes were built before 1919, against 15% in the typical UK town. In all there are 2 listed buildings. A conservation area has protected part of it since 1999. For its size the list is short: per resident, it has more listed heritage than only 10% of UK towns. Otherwise the figures are ordinary: David Davies (1888) was born here before 1900; and the list grew between 1999 and 2003.
Questions about Treharris’s history
How many listed buildings are there in Treharris?
Cadw lists 2 buildings inside Treharris’s built-up area: 0 Grade I, 0 Grade II* and 2 Grade II.
How many conservation areas are there in Treharris?
1, covering about 14 hectares of the town. The largest is Treharris.
How old are the homes in Treharris?
47% of homes were built before 1919 and 53% before 1940, from the Valuation Office Agency’s council tax records (March 2025).
Listed buildings, scheduled monuments and historic parks and gardens: Cadw, © Crown copyright, via DataMapWales.
Sources: Cadw listed buildings, scheduled monuments and registered historic parks and gardens via DataMapWales, October 2026, inside the ONS 2022 built-up-area boundary · Valuation Office Agency, Council Tax: stock of properties by build period (31 March 2025) · TownRatings grades: our own summary of the data, ranked against UK towns only · Cadw conservation areas via DataMapWales (October 2026). All under the Open Government Licence v3.0.
Contains public sector information licensed under the Open Government Licence v3.0. Contains HM Land Registry data © Crown copyright and database right 2026. Contains OS data © Crown copyright and database right 2026 (ONS boundaries). Northern Ireland: Source: NISRA; contains Land & Property Services data and Ordnance Survey of Northern Ireland information, © Crown copyright, licensed under the Open Government Licence v3.0. Scotland: contains National Records of Scotland data, Registers of Scotland data and SEPA data, © Crown copyright / © SEPA 2025, licensed under the Open Government Licence v3.0.