Could The Dark Tower by Stephen King have been inspired by Pico Cão Grande? This "volcanic plug" is in Obo National Park in the tiny island country of São Tomé and Principe off the coast of Africa. Photographs of this tower are hard to take because the top is usually in the clouds, but you'll find some good ones at Dark Roasted Blend. Link
(Image credit: Antonio Martins and Jose Bazelga)
No. Not it couldn't have.
Could it have been inspired by the poem "Childe Roland to the Dark Tower Came"?
Yes. Yes it could have.