When it came to imagining a new sports diving watch, Montblanc didn’t go to the world’s tropical waters for inspiration, but rather climbed up to the glacial lakes of the Mont-Blanc Massif. Ascending via the Chamonix Valley to the Mer de Glace (Sea of Ice), the Maison’s designers were captivated by the texture of the glacial ice with its interlocking network of crystals that have been frozen in time for millennia. Full with ideas, they returned to the Manufacture to try and figure out a way of translating what they had seen onto the face of a watch. This was no easy feat as not only had it never been done before, but a watch dial measures a mere 0.5 mm in height, making it very difficult to create the illusion of looking into the depth of a glacier. The Montblanc 1858 Iced Sea Automatic Date is more than a sports watch, it is a certified diving timing instrument, conforming to the ISO 6425 norm.