William Guise, later Sir William Guise, 5th Baronet of Elmore, travelled in Switzerland and Italy in 1764 in the company of Edward Gibbon, the historian. Two journals chronicling in great detail the first part of their tour, from Lausanne to Florence, Rome and other Italian cities, and the cultural sites and artefacts that they saw, have survived in the archives of Elmore Court, Gloucestershire, which was the Guise family home. Despite their historic and cultural interest, there has until now been no full transcription of these journals (totalling 83,000 words) apart from some references to them in an edition of Gibbon's diaries. As well as perceptive comments and opinions on the architecture, statues, pictures and other works of art which they saw, there are extensive references to military matters and fortifications; to the politics and governance of the towns of Northern Italy and to travel and lodging issues. The journals illustrate the serious nature of the Grand Tour as undertaken by Guise and his better known travelling companion, Edward Gibbon.