This snail is shaped like a flat coil, reaching 25 - 32 cm in diameter. Its colour is olive-brown to brown, and the leg and body are mostly darkish-blue. The head supports a pair of long filamentary tentacles, with the eye spots at the base of the tentacles.
The Great Ramshorn likes still or slow-moving water with ample vegetation, and is common throughout Europe and East Asia.
It feeds mostly on algae, detritus, and silt. The snail can carry dangerous flukes affecting fish and warm-blooded animals.