River Exe, river in southwest England, rising from its source on Exmoor in Somerset, only 5 mi (8 km) from the Bristol Channel, and flowing southward 60 mi across Devon to its estuary beginning at Exeter and into the English Channel at Exmouth. The Exe is an important river for angling (salmon and trout), and yachting is popular on the estuary. Upstream, there are paper and flour mills along its banks.