You will experience geological trekking, Oreum hiking, and Gotjawal walking where nature is alive on the beautiful volcanic island of Jeju. Geographically, Oreum is a type of monolithic volcano and is mostly a pyroclastic cone, or cinder cone. It is also called a parasitic volcano or side volcano in relation to Hallasan Mountain. A cone-shaped crater is a small, cone-shaped volcanic body created by pyroclastic materials released by an explosive eruption piled up around the crater. It is mainly composed of basaltic scoria and is usually around 50m in height. Scoria is a porous volcanic sediment and is called ‘songi’ in Jeju Island. Gotjawal is a place made up of rock formations, so the land is barren and difficult to use as arable land. It is also unsuitable for grazing, so most of it has been neglected, forming a natural forest area with tangled vines. However, recently, this Gotjawal area has been attracting attention as it has been compared to human lungs, such as ‘Jeju’s lungs’ or ‘nature’s lungs’ and is emphasized as the ‘lifeline of Jeju’s ecosystem’. Gotjawal was recognized as a barren land in the past, but today it is known to function as an environmental buffer between