The River Teifi (English: TY-vee; Welsh: Afon Teifi, pronounced [ˈavɔn ˈtɛivɪ]), formerly anglicised as Tivy, forms the boundary for most of its length between the Welsh counties of Ceredigion and Carmarthenshire, and for the final 3 miles (4.8 km) of its total length of 76 miles (122 km), the boundary between Ceredigion and Pembrokeshire. Its estuary is northwest of Cardigan, known in Welsh as Aberteifi, meaning 'mouth of the Teifi'.

Quelle: Wikipedia