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
Aluchin (volcano) soil on the lava flows and the growth of trees on them. This makes Aluchin one of the few continental Asian volcanoes with activity during the Holocene. The formation of the Alpha cone was characterized by an alternation of explosive and effusive activity. The Anyuy volcano lies farther north. Aluchin (volcano) Aluchin is a volcano along the Aluchin River in the Chukotka of Russia. The volcano was discovered in 1956–1957 by G.K. Kleshchev. The volcano is formed by three cones, named Alpha, Beta and Gamma, which occur along a fissure. Alpha, the main cone, formed within a river valley. It