The River Teifi is a river in west Wales. It starts in the hills above the town of Tregaron and then flows into a large marsh called Tregaron bog. This bog helps to stop flow in the river being too extreme. It stores up flood water when it is raining hard and it lets water go during dry weather.
The water in the River Teifi is very good quality. The river supports lots of wild-life including Salmon and Trout. The wildlife is so special that the whole river has been given special protetion by scientists to stop it being damaged.
The river passes through small towns such as Lampeter and Newcastle Emlyn before it reaches the sea at Cardigan. For the last few miles before it reaches Cardigan, the river runs through a deep gorge called Cigerran Gorge. Some people still fish for Salmon here using a very ancient boat called a Coracle.