Hallasan National Park (9.6 km), Seokgulam Trail (1.5 km), Gwaneumsa Trail (8.7 km), Donnaeko Trail (7 km), and Eoseungsaengak Trail (1.3 km). The longest trail is Seongpanak Trail which takes about 4.5 hours. Hallasan comprises 153.112 km of the Jeju Island. It rises 1.950 m above the sea level which means the highest mountain in South Korea. This mountain was formed in the fourth Cenozoic era by outburst of volcano. It is mostly composed of basalts. It is extending east and west, and it has high and gradual descent. On the other hand, the south part of the mountain is steep. In the
Hallasan at its top. The inclination and direction of the Tamra Formation of Baengnokdam cannot be measured directly at Baengnokdam, but it is N10W of slope and 30NE of slope measured near the valley below North Baengnokdam, 1,580 m above sea level. In order to understand the tendency of temperature change in Jeju Island, the short-term forecasting model of Halla, the weather data of the Korean peninsula, and the wind vector of AWS is analyzed. When the south winds flow into the sea, sea winds form around Hallasan, and the sea breeze is formed on the downwind side of the sea.