On Top of Enchanted Rock

Enchanted Rock is a batholith, which is just another word for "huge freakin' rock". A batholith forms when a huge glob of magma cools inside the Earth. The cooled rock is exposed when the soil and other such debris around it is eroded away.

It's called Enchanted rock because the Native Americans at the time heard the creaking that happens when the rock expands due to its heating by the sun, as well as it's contraction as it cools down by night.