Hallasan Hallasan Hallasan is a shield volcano on Jeju Island of South Korea. It is the highest mountain in South Korea. The area around the mountain is a designated national park, the Hallasan National Park ("Hallasan Gungnip Gongwon"/한라산국립공원/). Hallasan is commonly considered to be one of the three main mountains of South Korea, along with Jirisan and Seoraksan. Hallasan is the highest mountain in South Korea and is worshipped by people because they think that gods and spirits live on it. Alternate English names for the mountain include Hanla Mountain or Mount Halla and older English sources refer to the peak
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