Connecticut's Department of Energy and Environmental Protection says there are no reservations left for visitors looking to head to Squantz Pond State Park in New Fairfield.
DEEP says only people with prior reservations will be let into the park on Thursday; those who haven't booked yet will be turned away as the park will be at capacity.
The new online reservation system for CT state parks launched in the spring of this year to allow people to book for summer weekends and holidays.
DEEP says this is the first time that Squantz Pond has been fully reserved in ahead of a date.
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In addition to July 4, DEEP says Squantz Pond is also fully booked on Saturday, July 13.
The department encourages people who want to be outside on Thursday to visit Sherwood Island State Park in Westport or find other alternate options.