The two volumes of “jikjisimcheyojeol,” the world's oldest text printed with metal type as confirmed by UNESCO, have been restored.

The Cultural Heritage Administration(CHA), North Chungcheong Province and the city of Cheongju injected one-point-eight billion won since 2011 to restore the collection of Buddhist Zen teachings and treaties compiled by the Venerable Baekun of the Goryeo Dynasty in 1377.
 
The original volumes were printed in 1377 in Heungdeok Temple in Cheongju, North Chungcheong Province.
 
The restoration work was carried out in line with the lost-wax casting method, which uses a mold that is filled with molten metal and wax to create metal objects.

The jikjisimcheyojeol was formally added to UNESCO's Memory of the World Register in September 2001.