Pitfall: The Lost Expedition Cheats

Go to the title screen and HOLD L + R and press
Left, Up, Down, Up, B, Up, Up

Instead of hitting or kicking the pillars towards them, you can get your pick axes out and spin around by pressing Down then repeatedly pressing Right Analog-stick Up. Note: You are invincible when doing this, but you still need to be careful when Harry becomes dizzy. Quickly press A to stop being dizzy and start spinning again before they resume shooting at you.

Play as Nicole
Hold L+R then hit LEFT, UP, DOWN, UP, B, UP, UP.
Bottomless canteen
Hold L+R then hit LEFT, X, B, DOWN, X, A, X, B.
Hyper Punch Mode
Hold L+R then hit LEFT, RIGHT, B, UP, B, RIGHT, LEFT.
Unlock original Pitfall
Hold L+R then hit B, B, LEFT, RIGHT, B, X, A, UP, B.

Enter the following code at the title screen:
Hold L+R, press Left, Right, Left, Right, Y, Y, Y

Hold L+R then hit LEFT, RIGHT, B, UP, B, RIGHT, LEFT.

On each of the opposite ends of the closed door, there is a picture of a monkey inside a ring of fire. Light the bowls in front of the pictures to enter the Monkey Temple.