Got married two years ago in the IceHotel - inside the artic circle. Have fond memories of being in a church made completely of ice, wearing snow boots under a morning suit (with thermals underneath) and my wife turning up in a full wedding dress with a fur cape - looked stunning. Temperature wise, -10C in the church, and one night outside our heated wooden hunt the temperature fell to -40C. Have a picture of the temperature gauge.
Had minor frostbite on my nose after a snowmobile run to see the northern lights (40mph+ in temps of -25C with an exposed nose) and I still felt the cold. One day I vividly remember wearing 7 layers of clothing (including a full snow suit, then ski suit, and alternative layers of thermal clothing !). V funny but what an amazing experience. Completely unforgettable and highly recommended - so much so that we plan to go back at some point for our wedding anniversary (not sure which one).