Is there water on Mars?

Yes, there is water on Mars, but it is frozen under the north and south polar ice caps. The polar ice caps, which were once thought to be made up of only dry ice (frozen carbon dioxide), are now known to have water ice beneath a top layer of dry ice. Mars has a lot of flood and river channels suggesting that a long time ago liquid water flowed on Mars during a time when Mars was a warm and wet planet with a thicker atmosphere. There is recent evidence that there may also be liquid water at or near the surface on Mars in some places, but this has yet to be proven.