Westside Island
From the Sonic News Network, the Sonic Wiki
Westside Island (nicknamed the Island of Illusions) is the birthplace of Miles "Tails" Prower. The island was a relatively peaceful place until Dr. Robotnik decided to build the Death Egg there. Around the same time, Sonic was looking for a good place to have a holiday following the events of Sonic The Hedgehog on South Island. After he landed the Tornado on the island's Emerald Hill, he noticed an orange fox following him. Sonic tried to ditch him, but the young fox managed to keep up. The two started running around the hill until a helicopter occupied by Eggman came and transformed into a Drill Car. After defeating Robotnik, he told them of his plan to create his ultimate war machine, the Death Egg, powering it with the Chaos Emeralds. So Sonic and his new buddy Tails began their quest to destroy the Death Egg.
