Trust Regional Historic Environment Record
Pont Fawr Bridge, Llanrwst
Primary Reference Number (PRN) : 4618 Trust : Gwynedd Community : Llanrwst Unitary authority : Conwy NGR : SH7985061500 Site Type (preferred type first) : POST MEDIEVAL BRIDGE Status : Scheduled Ancient Monument , Listed Building I, Listed Building I
Summary : Pont Fawr in Llanrwst carries the road to Gwydir Castle over the river Conwy. It is also known as the 'Shaking Bridge' because it vibrates if the parapet is struck at a point above the central arch.
Pont Fawr is built of roughly coursed local slate and gritstone rubble and has three well-proportioned arches. The central arch spans 18m, and the side arches 13.5m. The width of the bridge, between the parapets, is 4m.
It was constructed in 1636, reputedly by Inigo Jones. The central and east arches are formed using sandstone. It was recorded that the west arch collapsed in 1675-6, and again needed rebuilding in 1702. The replacement arch is of poorer workmanship.
Stone panels are set into the apex of each parapet over the central arch. The southern parapet shows a panel bearing the Stuart arms and the date, 1636, on the outside of the bridge. The interior panel is plain. On the northern side, the weathered exterior panel shows the Prince of Wales' feathers, while the interior panel bears the date 1636. On the top of the southern parapet is a bronze sundial erected to mark three hundred years of the Llanrwst bridge.
Description : Also listed Grade II*.
Pont Fawr, bridge over the River Conway opposite Llanrwst, consists of three segmental arches, with cut-waters continued upwards to form triangular refuges. It is built of roughly coursed local slate and gritstone rubble. It was rebuilt in 1702. The original springers remain but the arch is of poorer workmanship. Stone panels surmounted by a double ogee capping are set in the apex of each parapet over the central arch. S side has Stuart arms and date 1636. Condition: good. <1>
As described in RCAHM. <2>
Repair work currently underway. (Davidson, 1988)
Construction of Llanrwst Bridge (Bont Fawr) began in 1636, and was a vital link for the Wynns of Gwydir, linking their estate with disparate portions of it at Caer Melwyr and Berth Ddu (Tucker 2002, 20). The bridge has three cutwaters, which are extended to coping level where they form refuges for pedestrians, and stone panels rise over the apex of the central arch. The south panel bears the Stuart Royal arms and is dated 1636. The west arch of the bridge collapsed in 1675, possibly weakened by damage to it sustained during the civil war, and emergency repairs were carried out (Gwynedd Archives, Caernarfon, Quarter Sessions Papers). Further repair work was carried out in 1703, when the western arch of the bridge gained its current appearance (Bingley 1814, 302).
The excavation at the western end of the Demountable 1 trench (Fig.7) was dug by the contractors to a depth of 1.1m below the modern macadamised road surface...A mid reddish brown sandy clay silt overlay the stones belonging to the foundations of the revetment wall  (Plate 3), which was built in 1794 (DRO QSD/AB/1/425(a). This was shown to overlie a stub of the bridge parapet of the Bont Fawr, dating from 1636  (Plates 2-4). This consisted of coursed rubble masonry, with blocks up to 0.8m square, and observed to a depth of 0.21m. Mortar samples from these two deposits have been analysed, and the results of this are shown in Appendix 2.
The identification of the parapet of the 1636 Bont Fawr indicates that there has been significant survival of the original angled bridged parapet, which is shown on the Buckler print (Fig. 3), and many other late 18th century images. Archaeological evidence for the raising of the river bank and the revetment wall in 1794 was also evidenced. (Evans, 2010)