At a Glance

A farmed volcanic crater on Jeju Island in the Republic of Korea can be restored to its predisturbance condition.

Project Description

The Hanon Maar Crater, on the Republic of Korea’s Jeju Island, was formed by volcanic activity millions of years ago. The crater originally held a volcanic lake protected by steep forested walls. Beginning about 500 years ago, humans converted the crater to agriculture, draining the lake with ditches and lowering a section of the crater rim to allow water to escape the basin. Today the native forest is largely gone from the crater and it hosts citrus groves and rice cultivation. Biohabitats was contracted to present a restoration master plan for returning the crater to its predisturbance state.

The restoration master plan included three key elements: restoring the damaged crater wall, restoring the lake to its historical size, and revegetating the entire crater with indigenous plants. Biohabitats created a plan with several alternative solutions to the problem of retaining the lake water, ranging from an earthen dam to a complete, terra-formed reconstruction of the original crater wall.

This ambitious restoration project came to international attention when Seogwipo hosted the World Conservation Congress in 2012. After that meeting, the IUCN passed a resolution supporting the restoration.
Now that the current low-intensity agricultural use is no longer viable, bringing back the lake and restoring native plants to the crater has the potential to establish the Republic of Korea as a leader in the stewardship of its natural resources.




Expertise Areas

Climate Change, Ecological Restoration, Urban Ecology, Water


The National Promotion Committee of Hanon Crater Restoration


Jeju Island, Jeju, Republic of Korea