Boldt Castle & Thousand Islands Boat Tour from Clayton

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Free cancellationTravelers' pick

1/17

Duration3h 30m

GroupUp to 50

LanguagesEN

Mobile ticketAccepted

A boat ride through two countries, one castle, and a century of island stories.

You board a naturalist-guided boat in Clayton and cruise 27 miles through the Thousand Islands, crossing into Canadian waters without needing a passport. The tour passes Wellesley Island, the Thousand Islands Bridge System, and Rock Island Lighthouse before reaching Heart Island, where you explore Boldt Castle on your own. Restroom on board, wheelchair accessible, and the guide handles the history so you can focus on the water and the islands.

3h 30m

Step-by-step itinerary

Thousand Islands boat tour and Boldt Castle

Start at Clayton, New York
Cruise among the 1000 Islands
Pass by islands, castles, lighthouses
View Millionaire's Row mansions
Travel under Thousand Islands Bridge spans
Pass Rock Island Lighthouse
View Rockport Ontario waterfront
Circle Wellesley Island
Enter Canadian waters north of Wellesley Island
Tour Boldt Castle on Heart Island
Return to Clayton Waterfront

The Experience

You don't need a passport to cross into Canada on this one, which is the kind of detail that matters when you're planning a day trip from upstate New York. The boat leaves from Clayton's waterfront at 39611 Chateau Lane, and within the first stretch you're already past Wellesley Island—the largest US island in the Thousand Islands region—heading north into Canadian waters toward Heart Island and Boldt Castle. The whole thing covers 27 miles of the St. Lawrence River, and the naturalist guide on board doesn't just point things out; they actually know the stories behind them. Pirates, bootleggers during Prohibition, the Gilded Age mansions that still line the water—it's the kind of history that makes sense when you're looking at the actual islands where it happened.

Boldt Castle itself is the centerpiece, and you get time to walk through it on your own once the boat gets you there. It's a self-guided tour, which means you move at your own pace, but the castle is the real draw—built by George Boldt as a monument to his wife, Louise, and it sits right there on Heart Island like something out of a different era. The boat also takes you under both spans of the Thousand Islands Bridge System, one on the US side and one on the Canadian side, and you pass Rock Island Lighthouse and the waterfront homes of Thousand Islands Park. The guide keeps the rhythm steady, and because the boat gets closer to the islands than most other tours in the area, you actually see the details—the architecture, the landscaping, the way these places sit in the water.

There's a restroom on board, which matters on a tour that runs long enough to need one, and the boat is wheelchair accessible if that's relevant for your group. Infants and small children can ride in a stroller or pram, and service animals are welcome. The one thing to know upfront: Boldt Castle admission isn't included in the boat ticket price. Adults pay $12.50 to enter the castle, children aged 5 to 12 pay $9, and kids under 4 are free. You can buy tickets at the blue ticket booth when you arrive, or call ahead to reserve them. Just plan to show up 30 minutes before departure so you have time to get your boarding pass and settle in.

What’s included

Your day includes sightseeing by boat from Clayton's waterfront, a local naturalist guide narrating the 27-mile route through the Thousand Islands, passage under both spans of the Thousand Islands Bridge System, views of Rock Island Lighthouse and Wellesley Island, and self-guided access to Boldt Castle on Heart Island (castle admission paid separately at the ticket booth).
Restroom on board.
No passport required.

Good to know

Easy physical levelWheelchair accessibleAccessible transportStroller friendlyPets welcome

Operated by Clayton Island Tours, LLC

Is this one for you?A good fit if you want to see Boldt Castle and the Thousand Islands without arranging your own boat—the guide and the fixed route handle the navigation and the stories. Arrive 30 minutes early for boarding, and budget separately for castle admission once you reach Heart Island.