As a part of the GCI's Maya Initiative—which focuses on advancing regional conservation practice and collaboration among the countries of the area—the GCI is involved in a partnership with the Instituto Hondureño de Antropología e Historia (IHAH) to develop a conservation plan for the hieroglyphic stairway at the Maya site of Copán in Honduras. The stairway, 10 meters wide by 24 meters high (30 feet by 75 feet), is composed of 63 steps with over 2,000 intricately carved Maya glyphs. It was rediscovered a century ago after being buried for over a thousand years.

A detail of the hieroglyphic stairway at Copán. Photo: William S. Ginell.

The GCI commissioned a measured survey to gather the precise data required to provide a condition evaluation, create a basis for site monitoring, and guide an intervention strategy. Digital photogrammetry was the survey method selected because of its capability of providing a precise map of the surface features. The site survey, which was conducted in June 2000, consists of two elements: overlapping stereo photography, done with a specialized survey (metric) camera, and survey observations recorded with a total station. Photarc Surveys of the United Kingdom was selected to carry out the photography, and the GCI staff gathered the survey measurements.

Measures were taken to protect both the stairway and the survey team and to ensure that contact with the stairway's stone surfaces was kept to an absolute minimum. Because the site is protected by a large tarpaulin suspended only a few feet from the surface, hundreds of camera setups were required to obtain the 1,500 photographs and over 3,500 control observations necessary to complete the project. The photography is already being used as a basis for the condition assessment. The data collected provide a unique record of the stairway and have the potential—by means of a digital photogrammetry workstation—to produce a three-dimensional model of the stairway to millimeter precision.