Chiricahua National Monument was established
in 1924 to preserve the mountain range, homeland of the Chiricahua
Apache. The Chiricahua Mountains rise above the grasslands of
southeastern Arizona. Dramatic rocky pinnacles were formed 27
million years ago when eruptions of the Turkey Creek Volcano
spewed ash over 1200 square miles. These superheated ash particles
melted together forming layers of grey rhyolite rock. Cooling
and subsequent uplifting created joints and cracks in the rock.
Eventually weaker rocks washed away, leaving innumerable spires,
balanced rocks and other shapes.