Treasure Mountain Easter Egg - Hidden Coins

On the bottom level of the mountain (the first one with the clubhouse)a rock tunnle cuts through the middle of the mountain. If you walk in, you can see two medium sized rocks. If you push "up" on the second rock, you will enter a secret tunnel with gold to the far right. Just walk by it to pick it up.

P.S. this can only be done once per game.