Angustus Labyrinthus is a unique region near the south polar cap. The squares formed by intersecting ridges earned the feature the informal name of the Inca City when it was discovered in Mariner 9 images in 1972. The linear ridges are believed to have formed by volcanic and tectonic forces, where magma filled fractures in the subsurface and then erosion revealed the magmatic material. Orbit Number: 84158 Latitude: -81.3484 Longitude: 296.938 Instrument: VIS Captured: 2020-12-03 20:45 https://photojournal.jpl.nasa.gov/catalog/PIA24408