New York
Thousand Islands Run
About this paddle route
The Thousand Islands are actually more than 1,800 islands scattered across the St. Lawrence where it leaves Lake Ontario, and the stretch between Clayton and Alexandria Bay is the densest and most photographed part of the archipelago. Boldt Castle on Heart Island is the centerpiece: a six-story Rhineland-style castle abandoned mid-construction in 1904 and later restored, reachable only by boat.
Clayton downriver to Boldt Castle and Alexandria Bay, through the St. Lawrence island channels.
Highlights
What earns the trip
- Boldt Castle on Heart Island, accessible only by water
- The Antique Boat Museum at Clayton
- Singer Castle and dozens of island cottages along the channels
- Protected river water with almost no fetch
Stops
- 1
Clayton
Upriver departure town, home of the Antique Boat Museum.
- 2
Boldt Castle
Heart Island, with dockage for visiting boats.
- 3
Alexandria Bay
The main harbor town on the American side.
When to go
Best time to go
June through September. Boldt Castle is open mid-May through mid-October.
Planner estimate for the mapped line: 46 min
Before you go
Know before you go
- The international border runs through these channels. Landing on the Canadian side requires reporting in.
- Shoals between the islands are numerous and poorly marked in places. Use current charts.
- Boldt Castle charges admission separately from dockage.
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