Cof Cymru: National Historic Assets of Wales · Wales
Canal Aqueduct over the River Twrch, Ystalyfera
Ystradgynlais, Powys, Wales
The record
- Designation
- Scheduled monument
- Site type
- Aqueduct
- Period
- Post Medieval/Modern
- Date of designation
- 8 November 1978
- Community
- Ystradgynlais
- Unitary authority
- Powys
- Country
- Wales
- Coordinates (centre of the scheduled area)
- 51.76834, -3.77992
- SAM number
- GM396
- Cadw record number
- 141
Slide toward Today to fade the historical sheet and see the modern map underneath.
David Rumsey Map Collection, Stanford LibrariesDavid Rumsey Map Collection, Stanford LibrariesDavid Rumsey Map Collection, Stanford LibrariesUniversity Library, Vrije Universiteit AmsterdamDavid Rumsey Map Collection, Stanford Libraries
Shown on 5 historical map sheets, the earliest the 1608 "(13) Cambriae Typus." (David Rumsey Map Collection, Stanford Libraries).
Cadw's description
Summary description and reason for designation
The following provides a general description of the Scheduled Ancient Monument.
The monument consists of the remains of an aqueduct, dating to the industrial period. This is the largest of the aqueducts which carried part of the original Swansea Canal, and it spans the Afon Twrch. The fast flowing nature of the river necessitated a weir to be built below the aqueduct to protect the piers and also to serve as a feeder. The total span of the aqueduct, which is built entirely of stone, is 21m.
The monument is of national importance for its potential to enhance our knowledge of industrial engineering and technology. It retains significant archaeological potential, with a strong probability of the presence of associated archaeological features and deposits. The structure itself may be expected to contain archaeological information concerning chronology and building techniques, together with a strong probability of environmental evidence. Aqueducts may be part of a larger cluster of monuments and their importance can further enhanced by their group value.
The scheduled area comprises the remains described and areas around them within which related evidence may be expected to survive.
Nearby in the register
- Canal Aqueduct over Afon Twrch, including weir (partly in Ystalyfera community)Transportunder 1 mi
- Canal Aqueduct over Afon Twrch, including weir (partly in Ystradgynlais community)Water Supply and Drainageunder 1 mi
- Bethel Independent ChapelReligious, Ritual and Funeraryunder 1 mi
- Wern Independent ChapelReligious, Ritual and Funeraryunder 1 mi
Other entries of the same register within about three miles of this one, by straight line.