There is a dry clay soil on Mars, and some ideas of producing brick have been advanced. There is also a volvacic stone which might be simply shaped somehow and used as a building material. A long valley is 3,100 miles long and 310 miles wide. Mountain named Olympus Mons is 78,000 feet high and the size of the state of Missouri at its base. Cliffs are four miles high.
Surface is scarred by lava flows and meteorite impacts.