The final two chimneys of the former Tamoil refinery in Collombey‑Muraz, canton Valais, were demolished on Thursday, as plans continue to redevelop the site into a hub for new technologies. +Get the most important news from Switzerland in your inbox The chimneys, about 100 metres high and with a total weight of 4,000 tonnes, collapsed one after the other, like a house of cards, within seconds. The demolition, which took about three months to prepare, required 50 kilos of explosives. Nearby streets were closed for one hour for safety reasons. “Extensive environmental, technical and risk analysis studies have been conducted since 2024 and field tests were carried out in 2025 to assess ground vibrations,” Tamoil Switzerland Director Stéphane Trachsler told reporters. The rubble will be reused in construction projects in the region. “It’s a symbolic day,” said Olivier Turin, mayor of Collombey-Muraz. “It closes an industrial chapter, but allows for a new beginning that will transform …