neighboring peaks  Lhotse , 8,516 m (27,940 ft);  Nuptse , 7,855 m (25,771 ft); and  Changtse , 7,580 m (24,870 ft). In 1856, the  Great Trigonometric Survey  of  British India  established the first published height of Everest, then known as  Peak XV , at 29,002 ft (8,840 m). In 1865, Everest was given its official English name