The Pre-Hispanic Road located at the Campus of Pontificia Universidad Católica del Perú (PUCP) is one of the few remains of the Qhapaq Ñan road system that crosses the city of Lima. Its 467 meters of two parallel walls that have withstood severe earthquakes can provide valuable information on the techniques used by the Ichsma (1100-1472 A.D.) and Incas (1472-1532 A.D.) in the construction. Centro Tierra-INTE, a PUCP research team and UNESCO Chair in Earthen Architecture, is conducting a study to gain an accurate knowledge of the material and the construction technique and to propose guidelines for the conservation of this type of earthen structures so recurrent in archeological sites of the Peruvian Central Coast. The interdisciplinary study includes a bibliographic, historical, archeological compilation, soil mechanic tests, structures laboratories tests, and electronic microscopy sweep assays. Conclusions with a conservation methodology for Ichsma and Inca archaeology sites are presented.