The main attraction at the new attraction is the snaking, glass-lined River Building, designed by Japanese architects SANAA.
The reviews from visitors were positive.
"I think it's a really astounding place for the community," said Nile Greenberg, from New York City who was visiting with friends. "I came up to see the building. I heard it was very beautiful. It's a very exciting project.
"I think it's a really astounding place for the community. It's a great place for architecture history, but also a new and exciting place."
A few things struck Greenberg about the building.
"You never really can see the entire building," he said. "You really only see parts around the place you're currently in ... in that way it sort of never ends.
"And in all these different pavilions, with really specific activities, that are sort of connected by this community group ... shared between them. And it's in one of the nicest settings I can imagine in New York or Connecticut."
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