The European edible dormouse or European fat dormouse (Glis glis) is a large dormouse and one of only two living species in the genus Glis, found in most of Europe and parts of western Asia. Its name comes from the Romans, who ate them as a delicacy.

The European edible dormouse is the largest of all dormice, being around 14 to 19 cm (5.5 to 7.5 in) in head-body length, plus an 11- to 13-cm-long tail. It normally weighs from 120 to 150 g (4.2 to 5.3 oz), but may almost double in weight immediately prior to hibernation. It has a generally squirrel-like body, with small ears, short legs, and large feet. Its fur is grey to greyish-brown in colour over most of the body, while the underparts and the inner surface of legs are white to pale buff; the line of demarcation is rather well defined.

Unlike most other dormice, they have no dark markings on the face, aside from faint rings around the eyes. The tail is long and bushy, with fur slightly darker than that on the body. Front feet have four digits and their hind feet have five. The soles of their feet are naked. Females have from four to six pairs of teats.

The edible dormouse is capable of limited autotomy; if another animal grasps the tail, the skin breaks easily and slides off the underlying bone, allowing the dormouse to escape. The exposed vertebrae then break off and the wound heals over, forming a fresh brush of hair.

The edible dormouse is found throughout much of mainland western Europe. It is also found on a number of Mediterranean islands, including Sardinia, Corsica, Sicily, and Crete. It is rather more sparsely distributed through central Europe and the Balkans, but can be found as far north-east as the upper Volga River. Close to the Volga River where small groups of the species are found at the Zhiguli Mountains, in Russia. They are also found in the Caucasus region. Germany has a small population of edible dormice within its borders, ranging from two to six individuals per hectare.

It is also found in scattered populations throughout Thrace, located on the southeastern tip of the European Balkan peninsula. In this region, two subspecies of the edible dormouse are found, G. g. glis and G. g. orientalis. Northern Anatolia has a different subspecies, G. g pindicus.

A small, isolated population of Glis glis also exists in south-east England. At the turn of the 20th century, the British banker and zoologist Lionel Walter Rothschild kept Glis glis in his private collection in the town of Tring in Hertfordshire; in 1902 some of the animals escaped and reproduced, establishing themselves in the wild as an invasive species. Today, the British edible dormouse population is thought to be 10,000 strong, and Glis glis have been recorded in a 25-kilometre (16-mile) radius of Tring, mostly concentrated to the south and east. The area of distribution has been described as a 200-square-mile (520 km2) triangle between Beaconsfield, Aylesbury, and Luton, around the southeast side of the Chiltern Hills.

A distinct group of dormice ranging from along the coastline of the Caspian Sea from southernmost Azerbaijan west through Iran to Turkmenistan, was formerly classified in G. glis. However, phylogenetic analysis found it to be a distinct species, the Iranian edible dormouse (Glis persicus). Significant divergence has also been noted among other populations of G. glis, probably as a consequence of the Messinian salinity crisis, and more species will probably be split in the future.

Edible dormice inhabit deciduous forests dominated by oak and beech, from sea level to the upper limits of such forests at 1,500 to 2,000 m (4,900 to 6,600 ft). They prefer dense forests with rocky cliffs and caves, but may be found in maquis vegetation, orchards, and urban margins. They have frequently been reported from caves as deep as 400 m (1,300 ft), where they can shelter from predators.

Population densities range from two to 22 individuals per hectare. Females inhabit only very small home ranges, of 0.15 to 0.76 ha (0.37 to 1.88 acres), but males occupy much larger ranges of 0.8 to 7 ha (2.0 to 17.3 acres), with several burrows.

Edible dormice are primarily herbivorous, feeding mainly on berries, apples, and nuts. However, they are adaptable, and have also been reported to eat bark, leaves, flowers, invertebrates, and even eggs. Beech mast, which is rich in energy and protein, is an excellent source of food for young and lactating females. Some dormice are found to have hair and ectoparasite remains in their stomachs, but this is mainly due to accidental ingestion during grooming.

Edible dormice also consume large numbers of beech tree seeds. A single, large, seeding tree within the home range of a dormouse can produce enough resources to support the energy requirements of reproduction. The location and age of a beech tree helps dictate where a population of dormice live, since older trees produce more seeds.

The individuals in this gallery were photographed in Vercors National Park, Southern France.