Arnus Vallis

{{Short description|Vallis on Mars}}

{{Infobox feature on celestial object

|name = Arnus Vallis

|image = 200px

|caption = Arnus Vallis Layers, as seen by HiRISE. Scale bar is 500 meters long.

|coordinates = {{coord|14.1|N|289.5|W|globe:mars_type:landmark|display=inline,title}}

}}

Arnus Vallis is an ancient river valley in the Syrtis Major quadrangle of Mars, located at 14.1° north latitude and 289.5° west longitude. It is 280 km long and was named after the classical and present day Arno River in Tuscany, Italy (previously named Arena Rupes).{{cite web|url=http://planetarynames.wr.usgs.gov |title=Planetary Names: Welcome |publisher=Planetarynames.wr.usgs.gov |date= |accessdate=2022-03-20}}

Image:Arnus Vallis layers.JPG|Arnus Vallis layers, as seen by HiRISE.