This view of the ruins of the De-chen jong castle, seen atop a large hill (also called De-ch’on jong in other sources), is from a collection of 50 photographs of central Tibet acquired in 1904 from the Imperial Russian Geographical Society in Saint Petersburg by the American Geographical Society. According to the photographer’s note, the castle ruins were on the way from Lhasa to the Gah-Idan monastery (also seen as Gah-Dan). The photographs in this collection were taken by two Mongolian Buddhist lamas, G.Ts. Tsybikov and Ovshe (O.M.) Norzunov, who visited Tibet in 1900 and 1901. Accompanying the photos is a set of notes written in Russian for the Imperial Russian Geographical Society by Tsybikov, Norzunov, and other Mongolians familiar with central Tibet. Alexander Grigoriev, corresponding member of the American Geographical Society, translated the notes from Russian into English in April 1904.