Venomous Snakes in Europe: Vipers and Where They Live

Europe’s venomous snakes at a glance

Europe has about a dozen viper species, depending on how taxonomists split them and where Europe’s eastern border is drawn. Vipers are thick-bodied snakes with long, hinged front fangs, usually vertical pupils and a zigzag or blotched pattern. Europe has no cobras, mambas or other elapids.

Lengths are typical adults from field guides; larger individuals occur. A few more vipers live at the edges of Europe, described below.

Common European adder

The common European adder (Vipera berus) has the largest range of any viper and lives farther north than any other snake, beyond the Arctic Circle in Scandinavia. Adults are usually 55–65 cm (22–26 in) long; the biggest, in Scandinavia, can exceed 90 cm (35 in). Males are usually gray or cream with a bold black zigzag, and females brown with a darker brown zigzag.

It is the only venomous snake in Britain, the Netherlands, Belgium, Denmark, Scandinavia, Finland, the Baltic states and Poland, and it is found in much of Germany, northern France and the mountains of the Alps and Balkans. Adders favor heathland, moorland, bogs, woodland edges and rocky slopes, and they emerge from winter dens as early as February on sunny days.

Adder venom is relatively weak and the snake injects little of it. Bites are painful and need hospital care, but deaths are very rare: Britain recorded 14 between 1876 and 2005, the last in 1975. Sweden, where adders are common, sees around 1,300 bites a year. Read more in are adders dangerous?

Asp viper

The asp viper (Vipera aspis) is the common viper of France, Switzerland and most of Italy, and it also lives in northeastern Spain, Andorra, northwestern Slovenia and a small area of the southern Black Forest in Germany. Adults average 60–65 cm (24–26 in), with males reaching 85 cm (33 in). The tip of its snout is slightly upturned, and its back pattern varies from crossbars to a broken zigzag; some individuals are almost black.

Asp viper bites are generally more serious than adder bites. In 2022 the IUCN moved the species from Least Concern to Vulnerable after estimating that its population had fallen by more than 30% over about 24 years.

Nose-horned viper: Europe’s most dangerous snake

The nose-horned viper (Vipera ammodytes) has a soft, flexible “horn” of small scales, about 5 mm (0.2 in) long, on the tip of its snout. It lives in northeastern Italy, southern Austria, Slovenia, Croatia and the rest of the Balkans, Greece, Bulgaria, Romania and Turkey, usually on dry, rocky, sunny slopes. Most adults are under 75 cm (30 in), and northern populations grow larger than southern ones.

It is often described as the most dangerous snake in Europe because of its size, fangs up to 13 mm (0.5 in) long and potent venom. Despite this, it is not aggressive, and most bites happen when people pick up rocks, reach into walls or step on a basking snake. Locally it is known as poskok in several Balkan languages.

Iberian vipers: Lataste’s and Seoane’s

Lataste’s viper (Vipera latastei) lives across much of Spain and Portugal and in northwestern Africa. It reaches about 72 cm (28 in) and has a small upturned horn on its snout. Habitat loss and persecution have made it Vulnerable, and it has declined in many areas.

Seoane’s viper (Vipera seoanei) replaces it in the humid north of Spain and Portugal and the far southwest of France. It grows to about 75 cm (30 in), and its pattern ranges from an adder-like zigzag to plain brown. It is listed as Near Threatened, mainly because of persecution and road deaths.

Meadow vipers: small and threatened

The meadow viper (Vipera ursinii) is Europe’s smallest viper, usually 40–50 cm (16–20 in) long, and one of its most threatened snakes. It survives in scattered mountain meadows of southeastern France and central Italy and in fragmented sites in the Balkans, Hungary and Romania. Its relatives, the Greek meadow viper (Vipera graeca) and the steppe viper (Vipera renardi) of Ukraine and southern Russia, have similar habits.

Meadow vipers feed largely on grasshoppers and crickets, have mild venom and rarely bite people. Their main threats are changes in grazing and mowing, afforestation, fire and illegal collection.

Vipers at the edges of Europe

• Blunt-nosed viper (Macrovipera lebetinus): on Cyprus. Elsewhere in its range, which stretches through the Middle East to Central Asia, females reach 1.5 m (4.9 ft), though Cypriot snakes are somewhat smaller. The closely related Milos viper lives on Milos and a few nearby Greek islands.
• Ottoman viper (Montivipera xanthina): northeastern Greece, several Aegean islands and European Turkey, usually 70–95 cm (28–37 in) long, with venom that has caused deaths.
• Caucasus vipers: several small vipers, such as Kaznakov’s viper, live in the Caucasus Mountains.
• Walser viper (Vipera walser): described only in 2016 from a few valleys in the Alps of northwestern Italy.

Europe also has a few mildly venomous colubrids with fangs at the back of the mouth, including the Montpellier snake of the Mediterranean, the cat snake of southeastern Europe and the false smooth snake of Iberia. Their venom is meant for lizards and small prey, and they are not considered dangerous to people.

Where to find vipers, country by country

• Britain, the Low Countries, Scandinavia, Finland and Poland: only the adder.
• Germany: the adder, plus the asp viper in the southern Black Forest.
• France: four vipers: adder, asp viper, Seoane’s viper and the meadow viper.
• Spain and Portugal: Lataste’s and Seoane’s vipers, plus the asp viper in northeastern Spain.
• Italy: the asp viper almost everywhere, plus the adder and Walser viper in the Alps, the nose-horned viper in the northeast and the meadow viper in the central Apennines.
• Balkans and Greece: the richest region, with nose-horned, adder, meadow and Ottoman vipers.
• No vipers: Ireland and Iceland, which have no native snakes at all, and islands such as Corsica, Sardinia, Crete and the Balearics.

How common are snakebites in Europe?

A 2012 review by Jean-Philippe Chippaux estimated about 1.06 venomous snakebites per 100,000 people a year in Europe, including European Russia and Turkey, or roughly 8,000 bites. Only about 15% were severe, and deaths averaged around four a year. In France, 36 people died from snakebite between 1980 and 2008. Most bites happen to the hands and feet of people who handle, catch or accidentally step on a viper.

Harmless look-alikes

• Grass snakes (Natrix): the grass snake and its relatives are long, slim, often olive with a yellow or white collar and round pupils. They often play dead when cornered. See adder vs grass snake.
• Smooth snake (Coronella austriaca): a small, harmless constrictor of heathland, often mistaken for an adder, with a dark stripe through the eye and a less regular pattern.
• Viperine water snake (Natrix maura): a harmless water snake of Iberia, France and Italy with a zigzag back pattern. It flattens its head and hisses like a viper.
• Slow worm (Anguis fragilis): the slow worm is a legless lizard, not a snake, with eyelids and a smooth, shiny body.

Staying safe around vipers

• Leave every snake alone. Keep your distance, give it room to escape and never try to catch, move or kill it. Vipers are protected in many European countries.
• Watch your step on sunny paths, heaths and rocky slopes, wear boots in the countryside, and do not put your hands into stone walls or under rocks.
• If someone is bitten, seek emergency medical help immediately: call 112 in the EU or 999 in the UK.