Ski past and to the left of the Owl Ski lift No6, toward a wire fence. Side-step up a bank of snow and you will find a hole in the fence. Go through and ski down the hill, make a sharp right to discover an ice cave. Come out the other end at the bottom of the slopes.
When you take pictures of your Miis or We Ski characters, you can import them to the Wii Message Board to be fooled around with and sent to all your friends!