Hallasan National Park summit, there is a crater lake called “Baekrokdam.” Since the mountain has high altitude, there are a number of alpine plants and animals. 1800 kinds of plants, including 400 kinds of specimen plants and 50 kinds of special plants, are living in Hallasan. So the Jeju island is designated by Biosphere Reserve in 2002 and Hallasan National Park is one of the region of Jeju Bioshere. Hallasan National Park Hallasan National Park () is located in the province of Jeju-do, South Korea. It was designated as the 9th national park in 1970. It features the highest mountain in South Korea,
Hallasan than in other areas, and the lowest temperature often appears at night. When the weak northwestern synoptic winds are blown, the lowest temperature appears in the eastern part of Jeju Island. The chill of the top of Hallasan descends downhill along the mountain range and is collected in the eastern part of Jeju Island so the morning temperature drops a lot. For the last five years, the deviation of temperature (maximum temperature - minimum temperature) increased in spring between March and May. The reason for the large deviation in spring is because the phenomenon occurs frequently by Hallasan. Hallasan was