The day was started to celebrate the places that make the state special for residents and visitors.
More than 200 tourist attractions across the state will welcome visitors with free or discounted admission or special offers. This includes museums, arts and cultural vendors and historical sites.
Anthony Anthony, Connecticut's chief marketing officer, says the day gives people the opportunity to learn about unique places to visit statewide.
Anthony says the participating attractions offer something for everyone.
"Whether you're a foodie getting into a restaurant or you get into a brewery - try some food. Get into the Connecticut Science Center and you want to allow kids to do some hands-on STEM projects. Or you get into one of our state parks or one of the other attractions that end up being an adventure. There's really so much to do," says Anthony.