Less impressive during daylight hours, but then the Ice itself has a great blue tint. I recommend arriving just before it starts to get dark, so you can experience both.
I went to both ice castles and 5 to 6 are not very busy. About 7 on it gets busy with lines making you wait in the wind. Bundle up, the breeze is the biggest issue.
I'd say go around 5:00pm right before it gets super busy for the night. That way you will be there also when it is lit up at night...very pretty!
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