Knothole

Knothole was the location of the Knothole Freedom Fighters home and acted as their main base of operations against Dr. Ivo Robotnik for many years. Hidden within the Great Forest, Knothole existed outside the polluted wastelands of Robotropolis and remained undiscovered for years. Upon the return of King Maximillian Acorn, and the rise of Dr. Eggman, Knothole became the new home of the Kingdom of Acorn.

Home of the Freedom Fighters
During the Great War, most of the children from Mobotropolis were sent to the sancturary of Knothole Village. When Dr. Robotnik betrayed the royal family and took over Mobotropolis, Knothole Village acted as the base of operations for the Original Freedom Fighters and later the Knothole Freedom Fighters, which was led by the king's daughter, Princess Sally Acorn. Robotnik made discovering its location one of his top priorities, as the Freedom Fighters acted as a thorn in his side for years. (StH: #1, #142, #143)

Kingdom of Knothole
After Sonic's disappearance and presumed death, Eggman formally declared war on both the Kingdom of Acorn and the Republic of Station Square. Knothole's location became known to the dictator, but over the course of a year, it became a bustling city and the new capital for the royal family. Forced to compete with Eggman's level of technology, Knothole featured a large amount of technology itself, including the Technolotree, the city's main means of global communication. (StH: #130)

Destruction
Dr. Eggman, tired of years of minor engagements with the Freedom Fighters and repeated failures, decided to destroy his enemies once and for all. He deployed his entire Egg Fleet and effectively wiped out all of Knowhole via aerial bombardment, and all but five of its citizens were captured and transported to the Egg Grape Chambers. However, the combined efforts of Sonic, Tails, Knuckles, Amy and NICOLE resulted in their rescue. NICOLE then reprogrammed Eggman's weapons to transport all of the former Knothole dezians to the nanite city, now known as New Mobotropolis. (StH: #175, #176, #177)