D.O. Nut Bridge is the sixth level of A Koopa's Revenge 2, or AKR2 for short. It is the first level to have water at the bottom.
- As the name suggests, there are many donut blocks, some of them make the form of a bridge.
- This level was renamed to Donovan Orville Nut (D.O. Nut) Bridge in version 2.9.
- There is a secret pathway that leads you to World 2-1.
To get there, near the end of the level, swim under the donut blocks (where the flagpole is standing) and the secret flagpole will be there for you.