The Cao Museum is located within the "El Brujo Archeological Site" on the Pacific Coast some 70km north of Trujillo in Peru. Since the arrival of the first nomads and hunters this sacred place, covering some 100 hectares, has been continuously occupied for over 5000 years. It sits besides the ocean on a plateau 6 meters above the fertile surrounding land. Thousands of years ago this was a sandbank with a mystical importance with has survived to this day. The Moche Civilization (0-800 AD) occupied El Brujo for more than 700 years and built two of the three "Huacas" (sacred adobe pyramids), Huaca Cao and Huaca Rajada. The third one, Huaca Prieta, is one of the oldest in South America: many remains of pre-ceramic peoples have been found there. The Cao Museum was built on an archeologically "clean" plot adjacent to an imaginary triangle joining the three Huacas. The visual perspectives, the direction of the wind and the sea were important factors determining the aesthetic and formal characteristics of the Museum. Its architecture seeks to be almost topographic, adapting itself to its surrounds rather than competing. Inclined roofs and slanted volumes play with contrasting light and dark forms and contours alluding to the importance of duality in the Moche culture. Exposed concrete is the only material used.