Climbing hills is fun. Who among us has the little voice at the start of a descent that says "It's too steep, you can't get down it."? I don't think so. But how many have found a climb that your little voice tells you you can't do? Then you get out of the saddle, and build up your cadence, and you pump and you gasp for air, and the bike rocks under you and finally, as you start to develop tunnel vision, you crest it and can relax a little. You look back at the hill and say to your little voice "Don't tell me what I can't do. I am unstoppable."