On September 20, 1770, the brothers Jean-André and Guillaume-Antoine Deluc, two scientists from Geneva, finally reached the summit of Mont Buet (3096m) after two unsuccessful attempts. From this vantage point overlooking the Alps and Mont Blanc, they performed several physics experiments and accumulated meteorological, geological, and ethnographic observations. The picturesque account of their ascent sparked further vocations: in the 1770s, the Genevans Marc-Théodore Bourrit, Horace-Bénédict de Saussure and Marc-Auguste Pictet also traveled to Mont Buet to replicate the Deluc's experiments and to make their own observations. These expeditions contributed to transform the mountain into a “laboratory of nature,” in Saussure’s own words. In September 2020, August 2021 and September 2022, two hundred and fifty years after the first ascent, a group of historians of science followed several paths to the summit of Mont Buet to reconstruct the historical expeditions of the Genevan scientists. They took with them two replicas of the barometer designed by Jean-André Deluc, they replicated the experiments of the 1770s and they documented their ascent with the help of a photographer, a draughtswoman, and a sound artist. In this talk, I will discuss the implications, the outcomes and the limits of this experience of historical reconstruction, focusing on three initial proposals of the project: 1) reconstructing scientific activity in the field, rather than in the controlled context of the laboratory; 2) capturing the mountain as a lived milieu rather than as a geographical location; 3) integrating historical research and scientific mediation by producing a contemporary archive that dialogues with the historical actors’ inscriptions (texts, engravings, drawings, and paintings).