There are as many as 10,000 mountains in S. Korea and they cover 70% of the country. Jirisan is the widest mountain within S.Korea, and is known for its rich soil and abundance of life. Hallasan is the highest mountain in South Korea but its soil is barren and not suitable for life. Seoraksan There are as many as 10,000 mountains in S. Korea and they cover 70% of the country. Jirisan is the widest mountain within S.Korea, and is known for its rich soil and abundance of life. Hallasan is the highest mountain in South Korea but its soil is barren and not suitable for life. Seoraksan is famous for its beautiful features. And there is a saying that a person who visits Seoraksan just once, cannot help but fall in love with it forever.