The city of Seoul will kick off a massive project next year to excavate what is believed to be the palatial site of an ancient fortification in the southern part of the capital, according to city officials Thursday.

The results of the project are widely expected to unveil the mystery over Pungnaptoseong, an ancient earthen fortress wall located in the south district of Songpa, southern Seoul.

Running nearly 3 kilometers at the southern edge of the Han River, Pungnaptoseong is speculated to have been the first capital of the kingdom of Baekje (18 B.C.-660 A.D.).

The city of Seoul has earmarked a budget of 125 billion won ($108 million) for 2016 for the excavation project, which will be focused on digging out some 22,000 square meters of the palatial site, the officials said.

The budget will be spent for the excavation work, as well as compensation for the residents who are now living on the ancient relic.

Part of the ancient wall was first found after a flood swept over the area in 1925. During the apartment construction work in 1997, a large amount of ancient remains and relics from the Baekje era were dug up, including earthenware and remains of public and residential buildings.

Currently, some 30,000 residents are residing in the inner part of the oval wall, and the city may need 2 trillion won in total to move all of them out of the relic site.

The city is now quickening efforts to relocate the residents and speed up the excavation project, the officials said, adding that Seoul is also planning to include the ancient site on the world heritage list of the United Nations Educational, Scientific and Cultural Organization by 2020.

"The project is aimed at uncovering the historical value of Pungnaptoseong and bolstering the status of the Seoul city," one city official said. (Yonhap)