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New York

Thousand Islands Run

Easy~15 mi river run3 stops
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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. 1

    Clayton

    Upriver departure town, home of the Antique Boat Museum.

  2. 2

    Boldt Castle

    Heart Island, with dockage for visiting boats.

  3. 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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