Mont Blanc massif led to calls to limit access to the most popular summits and for the mountains to be treated with greater respect. The Mont Blanc massif has provided numerous opportunities for academic research, dating back to the very first ascent of Mont Blanc in 1786 during which Michel Paccard carried scientific equipment to confirm it as the highest summit. In 1820, an ill-fated expedition led by Dr Hamel included pigeons intended for release at varying altitudes to measure the impact of reduced air density on their ability to fly. In 1890, Joseph Vallot built a small meteorological observatory at approximately between
Highest unclimbed mountain before been explored, especially since some high peaks in the Greater Ranges are so remote that they were unknown to local inhabitants when first sighted by European explorers. The world's third tallest peak, Kangchenjunga, has been summited a number of times, but after the first climbers of the peak agreed to honor the wishes of locals and not set foot on the topmost part of the mountain, succeeding mountaineering parties may have followed this tradition. Similarly, Nanda Devi has also been climbed but the topmost summit was not ascended and the primary summit is now off limits to climbers. Machapuchare