Sarn Helen
Coordinates: 53°16′55″N 3°49′41″W / 53.282°N 3.828°W
Sarn Helen refers to several stretches of Roman road in Wales. The 160 mi (260 km) route, which follows a meandering course through central Wales, connects Aberconwy in the north with Carmarthen in the west. Despite its length, academic debate continues as to the precise course of the Roman road. Many sections are now used by the modern road network while other parts are still traceable. However, there are sizeable stretches that have been lost and are unidentifiable.
The route is named after Saint Elen of Caernarfon, a Celtic saint, whose story is told in The Dream of Macsen Wledig, part of the Mabinogion. She is said to have ordered the construction of roads in Wales during the late 4th century.
In the north the route is believed to follow the western bank of the river Conwy from Canovium, a fort at Caerhun, passing through Trefriw, then leading on to Betws-y-Coed, with a branch leading to Caer Llugwy near Capel Curig. The route then passed through Dolwyddelan, running up the Cwm Penamnen valley and past the higher parts of Cwm Penmachno. The route then leads on past Llan Ffestiniog to the Roman fort of Tomen y Mur, near Trawsfynydd before continuing south towards Dolgellau.
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