The grass snake (Natrix natrix), sometimes called the ringed snake or water snake, is a Eurasian non-venomous snake.
It is often found near water and feeds almost exclusively on amphibians. The grass snake is widely distributed in mainland Europe, ranging from mid Scandinavia to southern Italy. It is also found in the Middle East and northwestern Africa. British grass snakes belong to the subspecies N. n. helvetica.
This species is one of only three snakes to occur in Great Britain, and is distributed throughout lowland areas of England and Wales; it is almost absent from Scotland, and is not found in Ireland, which has no native snakes.