Presentation, Interpretation, and Visitation Policy
After completion of conservation treatment in 2005 the GCI and DA began discussions on presentation and interpretation of the cave to the public and an appropriate visitation policy.
In consultation with lighting engineers in the United States and China, the project team has developed and implemented lighting of the cave. The final installation comprised several low voltage LED sources to illuminate the walls and ceiling of the main chamber. Simultaneous research is being undertaken on the light sensitivity of inorganic and organic colorants present in the cave and long-term monitoring of the stability of the wall painting pigments and colorants using International Organization for Standardization (ISO) blue scales textile fading cards and a lux data logger. This research will impact decisions on safe and acceptable light levels in other caves at the site.
Platform Concept and Design
Existing physical barriers to prevent visitors from touching the paintings are heavy glass screens in aluminum framing, with wheeled bases. Cave 85 has a large floor area, which enabled a different solution. Thus, the idea of a viewing platform that would raise the visitor above the floor level was conceived. The optimal height of the platform was determined to be 1.30 m above the floor level. This corresponds with loss of much of the lower painting register, yet allows for the statuary group to be seen unimpeded from the doorway and corridor. The steel structure of the platform and its steps rests on the cave floor; the surface is wood and is carpeted. The railings, which incorporate a tempered glass panel, define a platform space of 7.18 x 4.88 m. The platform also serves to carry the LED lighting system and interpretive panels, which were mounted in the four corners
Multiple objectives may be served by opening the cave to visitors. Foremost was the desire of the DA to convey a conservation message and enhance an understanding of what conservation entails and how it is done through creating a special experience. Visitors to the site generally recognize the fragility of the art and are beginning to be aware of the impacts of burgeoning tourism in China to cultural sites, but they have only a rudimentary understanding of deterioration processes and how they may be mitigated by a systematic conservation, management, and monitoring program.
To this end, five interpretive panels were created for the cave; four on the platform and one in the entry corridor. They focus especially on conservation issues and therefore supplement the normal tour provided by the DA guides, which is principally related to history and iconography (although the guides are increasingly being provided with conservation information to incorporate into their tours). The guides were asked for input both on content and location of panels.
The panels have photos, graphics, and written content (in Chinese and English) related to the Cave 85 conservation project objectives; materials and techniques of the wall paintings and sculpture; condition and causes of deterioration; conservation of the cave; and prevention and future monitoring. The panels are available as PDF files:
Cave 85 Project (4.1MB)
Wall Painting and Sculpture (12.8MB)
Condition and Causes of Deterioration (9MB)
Preserving Cave 85 (10.1MB)
Develop a strategy to manage visitation, including cave carrying capacity
The results of a multi-year study by the GCI and the DA on establishing a sustainable visitor carrying capacity for the Mogao Grottoes served as the basis for the visitor policy for Cave 85. Restricting conditions were established for caves open to visitation. These are: carbon dioxide levels not to exceed 1500 ppm (which relates to visitor comfort, health and safety) and RH not to exceed 62% (applicable to caves at risk from salt-induced deterioration, of which Cave 85 is one). RH is influenced mainly by intrusion of outside air through open doors and not by visitors' exhalation. Thus, during high humidity periods Cave 85 must remain closed to visitors. Humidity control through management practices is therefore essential for safe and sustainable visitation of the cave.
Page updated: March 2014