Based on the provided source material, there is no information regarding a city named Zummo in Nigeria. The source identifies "Zummo" exclusively as a surname.
Notable individuals with the surname include Bethany Zummo, an American sitting volleyball player; Frank Zummo, an American musician; Peter Zummo, an American composer and trombonist; and Vinnie Zummo, an American musician, producer, writer, arranger, and sound designer.