Oh, the confusion! The name Garreg/Gareg/Garregg was commonly used to describe the general area but has now dropped out of use; Ysgubor-y-Coed may once have been used as the name of a hamlet thereabouts but you'll find no signpost today with this name on it - although for some reason modern map makers still insist on marking it as a village between Eglwysfach and Furnace. The name Llanfihangel Capel-Edwin has disappeared; and Glandyfi was originally used only to describe the big house (Glandovey Castle) but is now the name of the village. I've wondered about all of this for ages, so did a bit of research and came up with the following:
There's an undated map in the Ceredigion Museum, Aberystwyth (prob late 1600s/early 1700s), entitled "A Map of that Part of Cardiganshire wherein are the mines belonging to ye Governor & Company of Mine Adventurers of England". Mention is made of "Garregg where we have a Key & 22 furnices" and "The Silver Mills wth 5 furnices".
The 1824 map produced by John Evans, Penygraig ("A New Map of the Vicinity of Aberystwyth"), clearly marks Gareg as the area by the riverside cottages and Glandyfi as the house further up the hill.
Garreg ("Rock") was used to decribe a destination during the old days of shipping on the Dyfi - Samuel Lewis's 1833 Topographical Dictionary of Wales states that "vessels of almost 300 tons can approach the wharfs at the small village of Carreg". One source states categorically that the name refers to a rock in the middle of the river. We are told that at least 4 ships were built there in the heyday of Dyfi shipping - one, in 1840, being named "Dart" - and the name Cei Goch seems sometimes to be applied to the wharfs. D.W.Morgan wrote in "Brief Glory" that there were smelting houses at Garreg, that the "silver mines of Garreg were financing Sir Hugh Middleton's schemes for giving London the New River", that the "glory of Garreg was short-lived and brilliant" and that "this peaceful loop of the Dovey...[is] named after the rock - covered except at low water - which lies in its deep pool".
In the general area, near that big bend on the Dyfi, there's still a Garreg Farm, a Coed-y-Garreg ("Garreg Wood") and a Pont Melin-y-Gareg ("Gareg Mill Bridge" - Gareg Mill was a corn mill). There was a "Garreg Gate", which was the old Toll Gate/Toll House. An elderly gentleman who has lived in the area all his life told me that cows used to be driven up from the market at Talybont so as to catch the tide at Garreg, and wade across to the farm on the north bank of the river. Old maps show a ferry at that point, too. So this establishes its general whereabouts, but you'll find no signposts announcing Garreg today, either.
Ysgubor-y-Coed ("Barn in the Wood") was reported in 1833 to be a hamlet along the Aberystwyth to Machynlleth road and the eastern bank of the River Einion near its junction with the Dyfi, its principal mansion being "Glandyvi". The hamlet was said to contain the "Silver Mills" - smelting houses and refining mills - and Eglwysfach chapel or Llanfihangel Capel-Edwin, dedicated to St. Michael. There were 700 or so inhabitants in the area, and the place was confidently expected to increase in importance even though its population was in decline. The reason for this optimism was the ability of quite large ships to navigate up to Garreg, and it was thought to be a place from which lead ore and bark could be exported, and timber, coal and limestone imported. In 1855, the term Ysgubor-y-Coed was certainly in use by the mother church at Llanfihangel Genau'r Glyn to denote both a township and a parish. So, on balance, it seems to me that the name Ysgubor-y-Coed originally included the linear villages which we now call Glandyfi, Eglwysfach and Furnace, but nowadays the name is reserved solely for the parish - the most northerly parish of Ceredigion.
Apparently the name Llanfihangel Capel-Edwin (Edwin's Chapel [belonging to] the Church of St. Michael) was in use well into the 19th Century, and referred to the village of Eglwysfach as well as the chapel - but where did the Edwin bit come from? As ever, there's an obscure folk tale telling how Edwin, King of Northumbria, tramped with his army into North Wales, crossed the river near Pennal, fought and won a battle at Llandre and afterwards camped on a bit of raised ground (today called Ynys Edwin) just the other side of Ynys Hir, and founded a chapel called, naturally, Capel Edwin. I can't find any reference to this except at:
http://www.cornardtye.freeserve.co.uk/egwi/egchurch.html - which contains some fascinating additional information on the area.
The name Glandovey/Glandyfi seems originally to have referred only to Glandovey/Glandyfi Castle, perched high up above the river bend. Glandyfi Castle was the home of George Jeffreys (1789-1868), who owned lands along the Dyfi and some of its tributaries. He and his wife, Justina (1786-1869), are buried in the churchyard of St. Michaels Church, Eglwysfach, and there's a memorial to his second son, also George (1820-1848), inside the church. A Charles and Robert Jeffreys emigrated to New Zealand in 1853. They eventually bought a 100 acre estate near Christchurch which they named Bryndwr, and they used the name Glandovey Rd - which still exists to this day. They returned to Wales on inheriting Glandyfi Castle. An Edward Jeffreys was mentioned as "of Glandovey" in 1869.
Nowadays, we know the entire village as Glandyfi, and the name Garreg has simply gone out of use. Maybe, with the coming of the railway and the dying out of the river trade, and the ultimate decline in quarrying and smelting thereabouts, the name associated with these activities similarly diminished in importance, and that associated with road and rail correspondingly grew.
The Furnace at FurnaceI came across an undated map - I think it was in the Wynnstay Hotel, in Machynlleth - that was entitled "A Map of that Part of Cardiganshire wherein are the mines belonging to ye Governor and Company of Mine Adventurers of England". Notes on the map state: "Garregg where we have a Key and 22 furnices", and "The Silver Mills wth 5 furnices" [sic]. I also noted down, at a location South of Talybont, "Is ye Lead Mills with 4 harths & as many pare of Bellowes drive wth one Wheele" [sic]. There's some useful information at:
Mention is made by Capt N. W. Apperley in "A Hunting Diary" (published 1926): "...the tumulus called Domen-las, said to be the grave of some prehistoric hero, near the river just under Glandovey Castle. This mound is about 24 feet in diameter at the base, the top being clad in trees...the country people did not care to meddle with the place, some superstition attaching to it".
I've dug up what I can about this structure, thanks to our helpful friends at Cadw, see: http://www.cadw.wales.gov.uk, and read about it in "A Guide to Ancient and Historic Wales: Dyfed", by S. Rees, published 1992 by HMSO. It's a 7m high motte, and 10m in diameter at the top of the mound. Three of the four sides are surrounded by a ditch, and there's a rectangular patch to one side which they reckon might have been a bailey. They go on to state that it was probably built by Lord Rhys in 1156 (so that'd be Rhys the Llys, I guess!), captured by Roger de Clare 2 years later, and subsequently recaptured by Lord Rhys again. So this tranquil part of the estuary, now within the Ynyshir RSPB Reserve and inhabited by herons, has seen some action in its past.
Elsewhere it has been suggested that it might also be the lost site of an early river crossing, and that's something I must research, as there's a persistent rumour that the Roman road, Sarn Helen, must have crossed the river in this general area.