Ollantaytambo, Peru (IMAGE) Geological Society of America Caption The Incas took advantage of pre-existing fractures in local stones to reduce the amount of energy needed to create their master stonework. Photo taken 21 July 2016. Credit Terri Cook and Lon Abbott Usage Restrictions Credit: Terri Cook and Lon Abbott. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.