There is a lot of water ice on Mars, comprising large geological features near the poles.
Found it! Ice on Mars
May 28, 2002: Using instruments on NASA's 2001 Mars Odyssey spacecraft, surprised scientists have found enormous quantities of buried treasure lying just under the surface of Mars -- enough water ice to fill Lake Michigan twice over. And that may be only the tip of the iceberg.
Meteorite Impacts Expose Ice on Mars
September 24, 2009: Meteorites recently striking Mars have exposed deposits of frozen water not far below the Martian surface.
If there are "large geological features" on the surface then that's news to me.
Got link? I'm interested now.