The larget outflow valley that emptied a large sea on the surface of Mars. The valley flows toward the small crater (Gusev); ca. 800 km long. Location on Mars: 21.8°S 182.7°W (https://en.wikipedia.org/wiki/Ma%CA%BCadim_Vallis).
This version is annotated with valleys (light blue) and large outflow channels (dark blue) that eroded the surface. These features are mapped and analyzed in this Nature article by Goudge et al., (2021): https://www.nature.com/articles/s41586-021-03860-1. Too see without annotations: https://skfb.ly/o8HsU.
Data: MOLA topography (https://tharsis.gsfc.nasa.gov/MOLA/mola.php) and THEMIS images (https://themis.asu.edu/)
Exported from QGIS (vertical exaggeration = 10).