Technically, yes, but for 99% of climbers in 2026, it is a two-day expedition. A "day climb" usually refers to the summit push starting from a high-altitude base like the Hörnli Hut (3,260m). The climb from the hut to the summit (4,478m) and back takes approximately 8 to 12 hours of non-stop, high-intensity scrambling and climbing. Most people spend "Day 1" hiking up to the hut to acclimatize and sleep, then "Day 2" is the actual 3:30 AM summit push. Only elite "speed climbers" or local Zermatt guides attempt the climb starting from the valley floor in a single day, as it involves an elevation gain of over 2,800 meters. A supportive peer warning: the Matterhorn is extremely exposed and technically demanding (Grade II/III). In 2026, guides are strictly regulated, and they will only take you for the summit push if you have proven your fitness and "sure-footedness" on other peaks first. It is not a "hike"; it is a serious alpine mission where the descent is often more dangerous and time-consuming than the ascent.