The Common Viper, also known as the European ADDER, is a venomous snake found throughout Europe and parts of Asia. It is the only venomous snake native to Britain and Ireland. The Common Viper is a medium-sized snake, typically growing to around 50 cm in length. It is usually grey or brown in colour, with a distinctive zigzag pattern along its back. It is an ambush predator, feeding mainly on small mammals, birds, and lizards.