Crater & Tower is based on Cheryl J. Fish's experience and research at Mount St. Helens Volcanic National Monument in Washington state in 2010, thirty years after the largest eruption in North America of the 20th Century. She was a writer-in-residence invited to join a group of scientists who measure changes there every five years. At the volcano, she was able to finally write about the traumatic events of September 11, 2001, that she had experienced close hand as a resident, mother, and teacher in Lower Manhattan, but had not been able to process. The two locales form a dialectic in these poems.