History of a Six Weeks' Tour through a part of France, Switzerland, Germany, and Holland; with Letters Descriptive of a Sail Round the Lake of Geneva and of the Glaciers of Chamouni is a travel narrative by the English Romantic authors Mary Shelley and Percy Bysshe Shelley. Published anonymously in 1817, it describes two trips taken by Mary, Percy, and Mary's stepsister, Claire Clairmont: one across Europe in 1814, and one to Lake Geneva in 1816. Divided into three sections, the text consists of a journal, four letters, and Percy Shelley's poem Mont Blanc. Apart from the poem, preface, and two letters, the text was primarily written and organised by Mary Shelley. In 1840 she revised the journal and the letters, republishing them in a collection of Percy Shelley's writings.