Neo Green Hill Zone (ネオグリーンヒルゾーン Neogurīnhiruzōn?) is the first Zone of Sonic Advance for the Game Boy Advance and Sonic N for the Nokia N-Gage. It is a slightly more updated, real world looking version of Green Hill Zone from Sonic the Hedgehog and closely resembles Emerald Coast from Sonic Adventure.
Neo Green Hill Zone begins on the beach and continues to the more forestry part of the area. Similar to Coconuts in Emerald Hill Zone from Sonic the Hedgehog 2, Kiki attacks from the trees here and there are also crab-like Badniks similar to Crabmeat.
At the end of Act 2, the character comes across a bridge and spots the mad scientist who turns around and flees. He then approaches the player who is required to then battle Dr. Eggman in the Egg Hammer Tank. When the player has almost beaten the machine, it will flip in the air when its hammer hits the ground. The player will only have to hit it one time to defeat the doctor. He then flees, dropping a Capsule with animal friends trapped inside.
- This Zone's name was supposed to be the original name of Aquatic Ruin Zone of Sonic the Hedgehog 2.
- The music of Act 1 is also remixed for Sonic Generations as a bonus unlockable track to listen to.
- A remix of Neo Green Hill Zone's music can be played in Events in Mario & Sonic at the Sochi 2014 Olympic Winter Games and Mario & Sonic at the Rio 2016 Olympic Games, where it appears under the title as "Neo Green Hill."