He was educated at Dover College and later Guy's Hospital in London, where he received training as a physician.
[1] In 1894, Koettlitz joined the Jackson–Harmsworth expedition to Franz Josef Land in the Arctic, as physician and geologist.
(Scott's forgotten Surgeon -AA Jones) In 1900 he travelled to Somaliland and Abyssinia with Herbert Weld Blundell.
[1] In 1901, Koettlitz volunteered for Robert Falcon Scott's Discovery Expedition to Antarctica, as physician and botanist.
For his role in the Discovery Expedition, Koettlitz was awarded a medal from the Royal Geographical Society.