Rabbits were very valuable animals in the medieval ages. Back then, rabbit meat was a delicacy, and their fur was an affordable alternative to an ermine’s fur, which was more expensive. This is why people did their best to breed them and protect them from the predators. This is where they bred the rabbits.
Back in medieval England rabbits were not bred in cages but in specially crafted earthen burrows called warrens, or pillow mounds. These were heaps of earth with multiple, well-ventilated inner chambers where rabbits mated, gave birth and raised their families. The pillow-like mounds were often built in oblong shape and sometimes were connected with each other with stone-lined tunnels. To prevent the rabbits from escaping, a field of pillow mounds was surrounded by a moat, or ditch filled with water. A fence provided protection from predators. Many warrens were accompanied by a lodge and a watchtower where the warrener lived.
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Pillow mounds are an obsolete technology, and the majority of these structures have long since disappeared. But there still hundreds of these scattered across the islands, especially in dry areas like Brecklands and Dartmoor where the soil is poor for crops but ideal for burrowing. Some of these are now protected by English Heritage.
More about this over at Amusing Planet.
(Image Credit: Bob Embleton/ Wikimedia Commons)