Even though I had been told that glaciers are deep blue, I was amazed when I saw it.  Water
is naturally a bit blue, but the color doesn't become obvious unless light travels through many
feet of it.  The glacier ice is so clear that the light penetrates a long way before reflecting
back.
We saw several large icebergs break off or "calve."  The noise made as they fall into the
water is
exactly like thunder.