Machu Picchu, Peru, satellite image. North is at top. The city is at centre, perched high up on a mountainside in the Andes, surrounded by forest and rivers in deep valleys. A road (centre right) winds up from one of these river valleys. This ancient city, built by the Inca civilisation from around 1460, is thought to have numerous examples of structures and ceremonial altars, such as the Temple of the Sun, that were aligned so that sunlight shone on particular areas on important astronomical dates, such as the solstices and equinoxes. Image obtained by the Ikonos satellite on 8 September 2003.