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The potential for damage to structures in Chaco Culture National Historical Park resulting from earthquakes, landslides, industrial blasting, road building and vehicular traffic has been investigated. The Historical Park, located in northwestern New Mexico, contains over 2,000 known archeological sites. The structures of interest, many of them multistory and a few containing over 200 rooms, date from the 11th and 12th centuries. Most of the remaining walls are 1.5 to 3.0 m in height, but a number exceed 5.0 m. A 2.0 mm/sec particle velocity is recommended as the upper limit for induced motions in the structures resulting from industrial blasting, road building and vehicular traffic. Minimum distances of these activities from the structures are recommended based on field recordings and analysis of the induced vibrations from these sources. Minimum distances of 1.2 km from blasting, 0.5 km from railroad traffic, 45 m from road building and 25 m from vehicular traffic are recommended based on normal blasting practices in the area, conventional rail traffic, usage of road building equipment and normal vehicular traffic patterns. Recommendations are also made for controlling vibrations from one road in the Historical Park considered to be too close to historical structures. Levels of expected ground motion from earthquakes, even for relatively short time periods of interest such as 50 yrs, indicate that possible future earthquake damage to the structures should be considered. The implication is that at least some of the past deterioration of the structures in the Historical Park may have been caused by earthquake ground motion.