40 original gelatin silver photographs of the Ryabushinsky expedition, taken in Central and Southern Kamchatka from May 1908 to September 1909. The photographs are mounted on two cardboards from both side with period black ink captions in Russian. They depict local landscapes, including mountains (Mishennaya Sopka), ranges (Valaginsky, Karakuli), rock formations (Kutkhiny Baty), rivers (Ozernaya, Kamchatka, Kroda-Kyg, Andrianovka), thermal springs (near Ozernaya River), and anabranches (Chabaevskaya and Antonovskaya). The photographs also depict the expedition members traveling from Milkovo to Petropavlovsk, with stops in Sharomi, Pushchino, and Ganaly. Also depicted are researchers at their winter base, driving dog sleds, resting by their yurt, conducting hydrographical experiments on the Khalaktyrsky River, overlooking Avachinskaya guba (with clearly visible “three brothers”), team members bathing in hot springs near Paratunki, sailing on the Ozernaya River, and posing by the overgrown lava flows. Also included are views of the now-extinct villages of Verkhne and Nizhne Kamchatsk, a fish drying booth in Milkovo, wooden houses in the village of Klyuchi, and fishermen catching salmon in the Kamchatka River.