The Voyage of the Beagle is a book written by Charles Darwin and published in 1839.
The Beagle sailed from Plymouth Sound on 27 December 1831 under the command of Captain Robert FitzRoy. While the expedition was originally planned to last two years it lasted almost five. Darwin spent most of this time exploring on land. The book is a vivid travel memoir as well as a detailed scientific field journal covering biology geology and anthropology that demonstrates Darwin's keen powers of observation written at a time when Western Europeans were exploring and charting the whole world.

Darwin's notes made during the voyage include comments hinting at his changing views on the fixity of species. On his return he wrote the book based on these notes at a time when he was first developing his theories of evolution through common descent and natural selection. The book includes some suggestions of his ideas.