Okay so it's not outdoors, but it's the next best thing, especially in Maine in the middle of winter.  The Maine Rock Gym is a specially designed and highly controlled area that allows people of all ages to safely experience the sport of rock climbing and to take it to what ever level they desire. All you have to do is walk through the door, and they take care of the rest. The best way to start is to grab a friend, jump in the car, and head on down to the Maine Rock Gym on Marginal Way in Portland. Once you are there the friendly staff will take you through a simple training course and you will be climbing in minutes.