The external appearance of Woolly rhinos is known from mummified individuals from Siberia as well as cave paintings. An adult woolly rhinoceros was 3.7 metres (12 feet) in length, and 2 to 3 tons on average, but they could probably grow to 4.3 - 4.4 meters (over 14 feet) at the largest. This is more than the modern white rhino. The Woolly rhinoceros could grow up to be 2 meters tall. Two horns on the skull were made of keratin, the anterior horn being 1 metre (3 feet) in length, with a smaller horn between its eyes. It had thick, long fur, small ears, short, thick legs, and a stocky body. Cave paintings suggest a wide dark band between the front and hind legs, but it is not universal and identification of rhinoceros as woolly rhinoceros is uncertain. The woolly rhinoceros used its horns for defensive purposes and to attract mates.
As the last and most derived member of the Pleistocene rhinoceros lineage, the woolly rhinoceros was supremely well adapted to its environment. Stocky limbs and thick woolly pelage made it well suited to the steppe-tundra environment prevalent across the Palearctic ecozone during the Pleistocene glaciations. Its geographical range expanded and contracted with the alternating cold and warm cycles, forcing populations to migrate as glaciers receded. Like the vast majority of rhinoceroses, the body plan of the woolly rhinoceros adhered to the conservative morphology, like the first rhinoceroses seen in the late Eocene. A close relative, the Elasmotherium had a more southern range.
Many species of Pleistocene megafauna, like the woolly rhinoceros, became extinct around the same time period. Human and Neanderthal hunting is often cited as one cause. Other theories for the cause of the extinctions are climate change associated with the receding Ice age and the hyperdisease hypothesis.
Its shape was known only from prehistoric cave drawings until a completely preserved specimen (missing only the fur and hooves) was discovered in a tar pit in Starunia, Poland. The specimen, an adult female, is now on display in the Polish Academy of Sciences' Museum of Natural History in Kraków. The woolly rhinoceros roamed much of Northern Europe and was common in the then cold, arid desert that is southern England and the North Sea today. During Greenland Stadial 2 (the Last Glacial Maximum) the North Sea did not exist as sea levels were up to 125 metres (410 ft) lower than today.
The woolly rhinoceros co-existed with woolly mammoths and several other extinct larger mammals.