Seaside Island

Bygone Island is a major location in the Sonic Boom series and where Sonic and his friends live. The island is shown to have various regions with climates and environments different from one another, such as a region of ice and snow neighboring a tropical forest.

Bygone Island is frequently attacked by Dr. Eggman from his his lair which lies just off the coast of the island.

Locations
The island has various regions, often different from one another, such as tropical forests, frigid and a desert canyon.

Sonic's Shack
Sonic lives in a simple hut-like shack on the beach, which does not contain many commodities besides a hammock and a table.

Tails' House
Tails lives on a hill at Seaside Coast in a hut, with windmills and waterwheels that he has created for sustaining energy for living. It is not too far from Sonic's Shack.

Amy's House
Amy lives in a round house by the ocean built on wooden platforms. It features a small garden with a lookout nearby.

Stick's Burrow
Stick lives in the jungle area not too far from the town at Seaside Coast. She made her home into the small hill and it is where she feels most safe from her paranoia. She has decorated her home with the collection of various items she has found.

Knuckles Hangout
Knuckles lives in a cave located at the Scrapyard where he exercises regularly to keep in shape.

Town
The town is where the inhabitants of the island live and is often targeted by Doctor Eggman's attacks, such as the Anti-fire Bot or a raid from the Danger Co. Deadly Equipment warehouse. It also has food court and a pet shop where Sticks found Buster (near the pet shop, in the rubbish) and adopted it as her own pet.

Sonic Boom: Rise of Lyric
Bygone Island is the second hub world area in Sonic Boom: Rise of Lyric. Here, the player can take up different side quests for Power Glyphs by talking with different residents and completing their given mission.

Other areas of the island beyond the town is the semi-dormant volcano which leads to Crater Lake. Another outside of town leads to the farmlands where Slowpoke Isle is beyond. Along the beaches outside the front of the town is Coral Bay which has the entrance to the Ocean Purification Plant and another secluded beach named Mystery Bay which leads to Creeper Gorge. Near the starting point of Bygone Island is a tower called the Seaside Harbor Light where you can access Sky Citadel.

North-east of Bygone Island is the desolate waste where Lyric chose to establish his lair at.

Sonic Boom: Shattered Crystal
Six major locations of the island are introduced. Sonic Boom: Shattered Crystal confirms that Sonic and his friends live on Seaside Coast of the island while Knuckles live in the Scrapyard which is the next location over from Seaside Coast. Other areas introduced are Shadow Canyons, Ancient Ruins, Volcanic Crater and above the island Cloud Sanctuary.

Trivia

 * As of yet, the island is not actually named in the TV series. However, it is identified in Sonic Boom: Rise of Lyric as it is one of the hub worlds in the game.
 * Bygone Island, or at least the whole overworld in Sonic Boom: Shattered Crystal is also unnamed.