Naejang means that something hidden in the mountain is infinite. The mountain is located in the boundary between Jeong-up and Sun-chang. It is one of the best mountains in Korea. And it has been famous for its fall foliage for more than 500 years. On 17 November 1971, the mountain became a national park. During peak season, there are about 100,000 tourists per day visiting, and there are around a million tourists per year. In the spring, there are cherry blossoms on the mostly green mountain. In the summer, there is ample shade from the trees. In the autumn, there is bright fall foliage. In the winter, there is snow. The mountain is very attractive in all four seasons. On the local trail map, Naejangsan mountain is marked Sinseonbong. It is possible to hike a circuit with 9 summits, all ranging between 622 and 763m altitude, in around 4-7 hours.