SIEM REAP — Basic fans, primitive bathrooms, frequent power cuts. These were the living conditions of Hans Leisen before Siem Reap province was opened to mass tourism in the 2000s.

Watch the interview on YouTube below:

Since 1995, the geologist and conservation scientist from the city of Cologne in Germany has worked on preserving and maintaining the structural authenticity of the many sculptures of the 12th-century Angkor Wat temple, which is of the most known monuments in Cambodia and internationally.

Thirty years ago, Siem Reap city and province were in the process of recovering from the years of war and conflicts that had devastated the country. But this did not stop Leisen and his team from embarking on a decades-long journey to revitalize the soul of Angkor Park despite the living situation, political and social challenges.

"We had to accept the conditions when we wanted to do something," he said.

In this 7th part of a two-hour interview, Leisen, who heads the German APSARA Conservation Project, shares with us how he managed the daily challenges as well as his recollection of a royal audience with the late King Norodom Sihanouk in Siem Reap city.

Background of the Conservation

The GACP is cooperating closely with the APSARA National Authority and UNESCO. Since 2020, the GACP team has been integrating into the APSARA authority within the framework of the APSARA-GACP cooperation project “German APSARA Restoration and Conservation Project GARCP”.

In 1997, GACP started with research, documentation and conservation of the precious decorations at Angkor Wat.

Conservation requires the exact knowledge of the materials - stone, brick and stuccoes - and the causes of deterioration. In the case of the stone reliefs, the extreme scale formation endangers the floral decorations and the mythological memory of the narrative reliefs.

Step-by-step documentation, research and practical testing paves the way for a sustainable conservation concept that satisfies the aesthetics appearance of the high-ranking works of art and the scientific approach, which is congruent with the current international state of the art.

Conservation materials are optimised and adapted to the needs of the monument. For stone conservation, the tetra-ethoxy-orthosilicate (TEOS) modular system is applied while for the stucco conservation lime products are developed.

At Angkor Wat temple, most reliefs are maintained and conserved. Other conservation work activities are carried out in more than 25 temples in the Angkor Park and beyond for example in Bakong and Preah Ko temples - where stucco remains and sandstone elements are conserved - as well as in many other sites in the Angkor Park, Koh Ker, and Sambor Prei Kuk and on Kulen mountain.

The research of wall paintings and polychrome decorations in the brick temples in Cambodia, construction and stone quarrying techniques are other topics of the Khmer-German GACP cooperation team.

The project is funded by the Cultural Preservation Programme of the German government, the TH Koln and FAKT.