Ben Nevis the summit only to find "fragments of earthen and glass ware, chicken bones, corks, and bits of paper". It was not until 1847 that Ben Nevis was confirmed by the Ordnance Survey as the highest mountain in Britain and Ireland, ahead of its rival Ben Macdhui. The summit observatory was built in the summer of 1883, and would remain in operation for 21 years. The first path to the summit was built at the same time as the observatory and was designed to allow ponies to carry up supplies, with a maximum gradient of one in five. The opening of
Ben Nevis used as a base for the many climbing routes on the mountain's north face. The hut is just above the confluence of Allt a' Mhuilinn and Allt Coire na Ciste. In addition to the main summit, Ben Nevis has two subsidiary "tops" listed in Munro's Tables, both of which are called Càrn Dearg ("red hill"). The higher of these, at , is to the northwest, and is often mistaken for Ben Nevis itself in views from the Fort William area. The other Càrn Dearg () juts out into Glen Nevis on the mountain's southwestern side. A lower hill, Meall an