Kratie, Cambodia © Oliver Townend
The Irrawaddy river dolphins inhabit a 118-mile (190km) stretch of the Mekong River. These odd but delightful creatures are in danger of extinction, with recent population estimates as little as 85, but are fortunately now protected. They are sometimes spotted from the riverbank but many tourists opt to rent small boats to get closer to them. The local oarsmen retain a healthy distance from surfacing animals but viewers can get close enough to recognise individual characteristics and see the famous dolphin smiles.
Address: Kratie, about five or six hours from Phnom Penh