I've always found Happy Isles Nature Center to be inconvenient. I have to walk to it from the shuttle stop and it's not on the way to the Mist Trail. The exhibits presented is informative but after the huge rock slide in 1996, I'm always afraid a piece of rock would break off Glacier Point and plunge into the nature center.
However, we visited on Halloween and I've come around and decided to like the Nature Center on the basis of that visit alone. On that Saturday night before Halloween, it became a magical place. Glowing carved pumpkins lined the pathway to the nature center. Rangers told spooky stories. There was a night-time treasure hunt. My kids ABSOLUTELY LOVED it.
Hope the rangers continue the tradition this year. On most days -- I would skip it if I'm in a rush to hike. But the Halloween program is one of the best funnest kid activity at Yosemite.
Hope this is helpful. If it is, let me know. Thanks!
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