In 1847 Strachey was appointed to a boundary commission of Jammu and Kashmir led by Alexander Cunningham. The third member was Thomas Thomson. The commission was set up to fix the boundary between Tibet and Ladakh. Raja Gulab Singh's forces had previously annexed Ladakh and invaded Tibet in 1841. The British deemed it important to formalise the boundary so as to prevent any future conflicts. However, the Tibetan authorities did not participate. Neither was the commission given permission to enter Tibet. The commission based itself at Leh, Ladakh. It eventually drafted a description of the boundary and retired. In 1848 Strachey was the first European to find the Siachen Glacier, and ascended it for 2 miles.