Elaphe quatuorlineata (common names: four-lined snake, Bulgarian ratsnake[3]) is a member of the family Colubridae.

[8] Four-lined snakes are found in Italy, along the whole western coast of the Balkan[9] peninsula, in the western half of Greece and many of the Greek islands, Macedonia (region), the southwestern corner of Bulgaria,[7] coastal Slovenia, coastal Croatia, Bosnia and Herzegovina, Montenegro, North Macedonia and Albania.

[7] The four-lined snake favours areas with a Mediterranean climate and is found in habitats featuring vegetation, stone walls, sparse woodland, forest margins and deserted buildings.

[5] Their behaviour is generally calmer than that of other snakes (seldom hissing or striking) and they are usually active in the morning and late afternoon.

[10] A large proportion of the snakes' diet consists of small mammals, such as rabbits, weasels, squirrels, and mice.