Grzegorz Gawlik on different continents and in different climates. Among other things, he discovered the highest lakes in the world on the Ojos del Salado volcano and found that the highest active volcano in the world is Llullaillaco. In addition, he explored more than 100 other volcanic sites such as geyser fields, geothermal fields, volcanic caves, volcanic deserts, volcanic plateaus, volcanic craters and cones, volcanic rock formations, lava fields. He climbed to about 100 peaks 4-, 5-, 6- and 7-thousand meters in the Himalayas, Andes, Pamir, Caucasus, Cordillera, High Atlas, Tanzania, Borneo and hundreds of lower peaks. During the expeditions, Gawlik explored
Siskiyou Mountains 1910, pears had begun to replace apples as the major fruit grown in the region. In 1927, the Jackson County seat moved to Medford, which had become much larger than Jacksonville. The highest peaks in the range include Mount Ashland at an elevation of , Dutchman Peak at , Siskiyou Peak at , and Wagner Butte at , all of which are in Oregon. The highest peak in the California portion of the range is Preston Peak at . There are also several lower mountains, including Negro Ben Mountain, which reaches . The main drainage basins in the mountains are