The aim of this article is to understand how the natural environment was described and perceived in Switzerland at the end of the 18th century. Taking the example of Georges Constantin Naville (1755–1789), a cultured traveller from a wealthy Genevan family, we examine the political and aesthetic conceptions prevalent in the city’s upper-class society in the context of the Enlightenment. Confidence in technological progress and enthusiasm for the efficient use of resources, considerations tinged with Protestant morality and the pre-Romantic influence of Rousseau are all elements that structure Naville’s diaries and reflect his contradictory perception of nature. By analysing the traveller-diarist’s discourse on the relationship between cities and mountains, this article, based on a presentation given in July 2022 at the 6th Swiss Congress of Historical Studies, highlights the paradoxes of enlightened thinking with regard to proto-industrialisation. The idealisation of an authentic mountain people with good and simple manners clashes with the changes observed in the rural economy and urban development, thus giving a contrasting image of Swiss society and the natural environment in which it evolves.