River Syfynwy

River Syfynwy (Welsh: Afon Syfynwy, Syfnwy or Syfni) is a river entirely within Pembrokeshire, Wales, rising in the Preseli Hills, feeding the Rosebush and Llys y Fran reservoirs and joining the Eastern Cleddau to the south. It is a river considered to be important as an ecological indicator and part is in a site of special scientific interest.

Course

The river is formed by the confluence of several streams rising in the southern slopes of the Preseli Hills at some 350 metres (1,150 ft) and flows southwards into Rosebush Reservoir, where it passes through or over the dam. Cascades, Syfynwy Falls, are immediately below the dam and are a visitor attraction when the reservoir is overflowing. Continuing south west, the river flows through a wooded valley - Holmus Wood, Farthing's Hook Wood and Dan-y-Coed, then under the Grade II-listed Farthing's Hook Bridge. It runs between Pen-yr-Allt Wood and Velindre Wood before entering the northern end of Llys y Fran reservoir. This reservoir's dam produces electricity. After the dam, the river flows in a more southerly direction before turning south east, passing under Step-aside Bridge, near Clarbeston, and the 18th century Grade II-listed Gelli Bridge at Gelli Hill to meet the Eastern Cleddau.