Valles Marineris

== English == === Etymology === From Latin vallēs (“valleys”) + pseudo-Latin genitive of English mariner. === Pronunciation === IPA(key): /ˈvælɪs ˌmɛəɹɪˈnɛɹɪs/ === Proper noun === Valles Marineris a large system of canyons on the surface of Mars; contains channels possibly caused by the flow of water