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
Jocotitlán (volcano) activity in the region is. If it erupts, the volcano could pose a serious threat to Greater Toluca and even Greater Mexico City. The volcano can be easily climbed from the town of Jocotitlán. A winding 19 km country lane leads up to the microwave antenna located near the summit. Jocotitlán (volcano) Jocotitlán, also known as Xocotépetl (), is a volcano in the Jocotitlán and Atlacomulco municipalities, in the State of Mexico. At above sea level, its summit is the 12th highest peak of Mexico. Jocotitlán volcano lies in the northern part of the Toluca Valley. It is part of