Its main summit, named "Dufourspitze" in honor of the surveyor Guillaume-Henri Dufour and wholly located in Switzerland, culminates at and is followed by the five nearly equally high subsidiary summits of Dunantspitze, Grenzgipfel, Nordend, Zumsteinspitze, and Signalkuppe. Some other over 4000 m peaks such as Piramide Vincent, Punta Giordani, and Corno Nero are wholly in Italy. Monte Rosa is the highest mountain of both Switzerland and the Pennine Alps and is also the second-highest mountain of the Alps and Europe outside the Caucasus.