There is a well, Ffynnon Helen, up the road near Caernarfon; an old long distance Roman road which passes through the area carries the name Sarn Helen, in the belief that she commissioned its building.
The history of Helen, presumed a local saint, has spread itself far and wide, becoming intertwined with those of other saints and deities from across the Christian and pre Christian world. She is made heroine of one of the later Mabinogion stories, The Dream of Macsen Wledig; and is claimed by wider British mythology, her story becoming confused with that of Helena of Constantinople. Helen is cited as the alleged discoverer of Christ’s Cross, and actual mother of Constantine, first Christian ruler proclaimed emperor at York, There are more wells dedicated in Britain to St Helen than to any other, non-Biblical saint. 
Dolwyddelan lies on the A470 south west of Betws y Coed, under the shadow of its impressive Welsh castle.There was a belief that the name Dolwyddelan itself was derived from Dolydd Elen – Elen’s Meadow. The village more likely owes its name to St Gwyddelan, the Irish associate of Beuno who we met previously at Gwyddelwern and to whom the church here is dedicated. His original chapel was set up on the nearby hillside of Bryn y Bedd in around 600AD.
Despite this, the connections with Helen continue to run deep, a Methodist chapel first established in 1783 bears the name Capel Elen and the hotel beside the well is called Castell Elen.
But is the well Ffynnon Elen or is it Ffynnon Elan? The historical record prefers the former. Francis Jones  and the Gruffydds  both use Elan and both give an alternative dedication to Gwyddelan himself, citing Myrddin Fardd. For no other reason than choosing to follow the larger crowd we have used Elen for now, though we are obviously open to offers to change.
In recent years the well here has suffered various attacks of nature. Trees growing close to the site were observed some 20 or 30 years ago to be spreading their roots into the well structure, displacing stones and leading to landslips around the well. Recently the most invasive of these trees have been removed to protect and stabilise the well; however problems with access means that the site is difficult to visit and maintain.
I asked a passer by near the church whether he knew of the well and for directions to it. He immediately directed me to a small, stepped, pathway leading off the main road through the village between the hotel and the next door chapel. This path leads directly up to the well which lies some 50 yards up a steep hill beside the road. As I understand it though, the owners of the land across which the path runs have forbidden its use, it is not marked as a right of way, and although this path appears to have as its sole purpose giving access to the well, indeed North and Hughes state (in 1924) that this path is the access to the well , today the primary access is supposedly through the gardens of the hotel.
As a result rescue work on the well has been hampered and the site is, during my visit at least, almost totally buried beneath undergrowth and ferns. Beneath all of this it was just possible to make out the remaining stonework and structure, and to note that water still flows into the well, possibly being directed away through blue plastic pipes which cross the site.
Ffynnon Elen has a long history. Legend has it that Roman soldiers used it as a picnicking site, and possible Roman coins have been found close to the well in excavations. Excavation has also shown evidence of a road close to the well suggesting that the road through the village at one time ran much closer to the well.
The Royal Commission visited the well in 1956, recording that it consisted of
“A small rectangular basin now dry, 9ft by 7ft with walls of earth-mortared rubble, on ground sloping steeply to the south. The south wall is 1ft 6 ins thick and 1ft high; the remaining walls are revetments only, that on the north side reaching a height of 4ft; water emerging outside the south wall is now collected in a drinking trough. The name has also been applied to a natural spring about 100 yards to the NW. Condition; ruined and overgrown”
At some period in its history, the well was surrounded by a small stone basin, itself in a rough stone built well house, some nine feet by eight and a half. A narrow pathway ran around the well within the building. A sketch on the information board in the car park for Dolwyddelan Castle shows the shape of the remains of the well in better days.
The water entered the well from a spring to the north and flowed away in a stream towards the road to the south. It was noted for its tendency to steam during cold weather. The waters were noted as particularly efficacious for weak children and for paralysed limbs. The Gruffydds record an account of one old woman, sometime in the twentieth century, who feeling weak would ask for water from the well to drink, which she claimed strengthened her. 
It is to be hoped that access arrangements can be agreed for the well. Apparently grants have been secured to restore the well and to provide interpretation for the site. Much remains of the basic structure, and water does seem to flow. It would be a great pity if such a monument were to be lost for such a trivial reason.
 Graham Jones (2012) Wells of St Helen: A told and untold story. Paper given to the Well springs conference, Caerleon, September 2012
 Eirlys and Ken Gruffydd(1999) Ffynhonnau Cymru vol 2. Gwasg Carreg Gwalch
 Francis Jones(1954) Holy Wells of Wales, Cardiff University Press
 Herbert North and Harold Hughes(1924) The Old Churches of Snowdonia, Bangor