Why was tucson named tucson in Arizona?

When the Spaniards arrived at the Tucson area the native Tohono O'odham called it Chuk-Son. The Spanish imitation of this word has morphed since then to Tucson, but it means basically "spring at the base of a black mountain." The "black mountain" is the Tucson mountains, which contain volcanic rock that varies from red to black. Now much of these mountains are preserved in the Saguaro National Park.