Valley of Bowser 1

Valley of Bowser 1 is a cave level with a very maze-like structure in the Valley of Bowser of Super Mario World. It can be accessed by the completion of Sunken Ghost Ship, and its completion unlocks Valley of Bowser 2.

Layout
The level begins with a Mega Mole, trapped in red ! Blocks if the red ! Switch has been activated, followed by a Chargin' Chuck. Right after this is a labyrinth, with short, different paths. The lower path takes Mario to an enclosed area with a Chargin' Chuck, who must break the Grab Blocks and defeat a Mega Mole for Mario to earn a Dragon Coin. The other, upper path is guarded with Mega Moles, before the path diverges into two once more.

This upper path has a Mega Mole guarding another Dragon Coin. The lower path takes Mario to two more routes. The lower path contains a Mega Mole and a flooded gap. The path straight ahead contains three Chargin' Chucks who break the yellow blocks containing them. This is to be followed by the paths diverging yet again. The lower path takes Mario to a green ! Block, containing either a Super Mushroom or Fire Flower. Here, there is also another Mega Mole and two yellow blocks, leading to the upper path where another Mega Mole waits. The lower path leads to another Mega Mole and a pit, covered with breakable blue blocks Chargin' Chucks may break.

The upper path includes two Mega Moles and a green pipe. The previous upper path includes two Mega Moles and a flooded gap before leading to the Midway Gate. The upper path here contains two Mega Moles and a gap with Munchers. Mario may then head downward or straightforward. The straightforward path takes Mario to a 3-Up Moon, while the other path takes him to a blue ! Block before Mario reaches five different paths.

The upper path takes Mario to yellow blocks broken by a Chargin' Chuck followed by three coins. Below is a Dragon Coin and a Mega Mole, surrounded by yellow ! Blocks if activated. Below is a normal path and a gap with a Dragon Coin. From here, Mario can activate Hidden Blocks to access the other path. The lower path includes a Mega Mole and a bottomless pit. The alternate path ends with yellow blocks destroyed by Chargin' Chucks. After this, the path diverges into four.

In the middle is a yellow block containing a Super Mushroom or Cape Feather. Cape Mario is able to access a blue pipe up above, leading to an item minigame. Exiting the minigame takes Mario to a green pipe. The second path leads to a Mega Mole and blue breakable blocks broken by Chargin' Chucks. Below this is only a Mega Mole, with both paths leading to the final Dragon Coin in the stage. The lower path ends with a green pipe which takes Mario directly to the Giant Gate, allowing him to complete the level and unlock Valley of Bowser 2.