Reaching the Cannon in World 2 (New Super Mario Bros. DS)

World 2 Cannon unlocks World 5. Located in World 2-3.

Exact Steps

1. Play World 2-3 normally until the first Star Coin (after the midway flag).
2. Continue right — you'll see a green pipe on a ledge above a gap with two Koopa Troopas.
3. Do NOT enter the pipe. Instead, jump on the Koopas to reach the ledge above and right of the pipe.
4. There is a hidden ? Block (invisible) at the edge of that ledge. Jump to hit it → vine grows.
5. Climb vine → secret area → Red Flag (secret exit).
6. Complete secret exit → Cannon cutscene → World 5 unlocked on map.

Requirements

• Mini-Mario or Shell helps fit tight gaps, but not required — normal Mario can hit the block with precise jump.
• Starman is not required for this cannon (that's World 1 Cannon / World 4).

Visual Aid

Search YouTube: "NSMB DS World 2 Cannon secret exit" — 30-sec walkthroughs show exact jump arc.