If you eat shaved ice very fast you will get brain freeze.
かき氷を早く食べると脳が凍ってしまいます。
Me and my colleagues lived in a small 2 room cabin built on the edge of a cliff on the mountain. I say 2 rooms, but besides the entrance, there was a 6 by 2 tatami room. We ate potatoes, dried fish and tofu. Because we were on the top of a cold mountain, the potatoes would freeze during the winter.