The grounds are always free to walk around. The fort and museum are closed during the winter, but normally admission is $6 (cash only). CT Charter Oak pass is accepted for free admission. Additionally, there are admission deals when a water taxi ticket is purchased, be sure to ask the staff for more details. The website also has the prices for children (cheaper than $6).
There is a sign that lists a $5 fee. But no one walking around to make sure you paid?? So I'm not sure what that was about?? Maybe certain times of the year or certain buildings?? But it was a beautiful site.
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