In 1804 he travelled to British Guiana to take charge of his uncle's estates near Georgetown. In 1812 he started to explore the hinterland of the colony, making four journeys between then and 1824, and reaching Brazil walking barefoot in the rainy season. He described his discoveries in his book "Waterton's Wanderings in South America", which inspired British schoolboys such as Charles Darwin and Alfred Russel Wallace. His explorations laid to rest the persistent myth of Raleigh's Lake Parime by suggesting that the seasonal flooding of the Rupununi savannah had been misidentified as a lake.