CH-QUAT Excursion 2025
Ticino and Northern Italy
Organised by Marc Lütscher (ISSKA)
With contributions from Cristian Scapozza (SUPSI) and Sarah Kamleitner (University of Lausanne)
From September 19–20, 2025, the annual CH-QUAT excursion took place. This year, we focused on the Quaternary history of Ticino and northern Italy. The excursion began on Friday evening with a walk through Capo Lago and Riva San Vitale. There, Cristian Scapozza gave us an introduction to the local geology and an overview of the various glaciers and their complex interactions that shaped the area around Lake Lugano during the ice ages. In this context, we also discussed the development of the lake level. A witness to a former lake level is the baptistery in Riva San Vitale, which lies noticeably lower than today’s flood level. We ended the evening with a convivial dinner in Capo Lago.
The next day, we continued to northern Italy, where we followed the traces of the Last Glacial Maximum (LGM). At Alpe Cana, Sarah Kamleitner presented her study on the Ticino-Toce glacier. There, we examined five lateral moraines that had been dated using cosmogenic nuclides. This chronology provided fascinating insights into the dynamics and fluctuations of the Ticino-Toce glacier during the Last Glacial Maximum. We also discussed the glacier’s different catchment areas and flow directions, which were determined based on the lithology of erratic boulders. Via Stresa, we returned to Ticino, to Ronco sopra Ascona. Overlooking Lake Maggiore, Cristian Scapozza explained how this landscape has changed with glacier advances and retreats. Nearby, we observed glacially polished rocks high above the lake. The day ended with a pleasant dinner and engaging conversations.
The final day of the excursion took us to the Blenio Valley. Here, Cristian Scapozza guided us on a historical hike. The hike began at the church in Malvaglia, where the inscription “exitus lac maioris” could be read, already hinting at the main theme of the walk. The path led us past several castles and fortifications that are still preserved today, allowing us to gain an overview of the different phases of settlement history in the Blenio Valley. The local population was also affected by a lake that formed after a landslide around 1513, flooding numerous villages. The lake level at that time was recorded in Semione. In May 1515, the natural dam broke, and the resulting flood (Buzza di Biasca) destroyed buildings and structures in the surrounding area and claimed many lives.
To conclude the excursion, we stopped for lunch at a typical Ticino grotto. With many new and exciting impressions from geology, archaeology, and history, we began our journey home.