Turner inverted the sketchbook to make this sketch. Together with another sketch on folio 23 verso (D04761), this served as the basis of the watercolour Chateau de Rinkenberg, on the Lac de Brientz, Switzerland, which Turner made in 1809 for Walter Fawkes (Taft Museum, Cincinnati, Ohio).1 Fawkes’s first documented purchase of a work by Turner was the watercolour Glacier and Source of the Arveron, Going up to the Mer de Glace (National Museum of Wales, Cardiff),2 from the Royal Academy in 1803. He went on to acquire almost all the watercolours that Turner made from his 1802 material until as late as 1820. Turner made an intermediate drawing of the Ringgenberg view in his Grenoble series (Tate D04539; Turner Bequest LXXIV 46), from which Fawkes may have chosen the subject. Turner saw the castle, on the north shore of the lake facing west towards Unterseen, on a day’s excursion by boat from Brienz. He spent a day or two in the town after visiting the Reichenbach falls, for which see folio 27 of this sketchbook (D04766), and Meiringen before moving on to Lucerne.