World 4 (Super Mario World 2: Yoshi's Island)
From the Super Mario Wiki
World 4 is the fourth world of the game Super Mario World 2: Yoshi's Island and Yoshi's Island: Super Mario Advance 3. It consists of 10 levels, and it has 6 regular Levels, a Fort, a Castle, a Extra Level and the Match Cards Bonus Game. The world's theme is a sunset plains in autumn.
 List of Levels