The island of Sakhalin, situated at the eastern edge of Eurasia, is a unique region of Russia, and is home to a number of interesting plants. 75% of this large island (which measures 943 km from north to south) consists of hills and mountains, and the presence of large water reservoirs have a considerable influence on the climate. Snow cover here is deeper than on the mainland, and sudden changes of temperature can occur during all seasons. The winter here is comparitively mild and long, followed by a cold protracted spring, moist cool summer and prolonged warm autumn.