Official Boldt Castle Website - Alexandria Bay NY in the Heart of the 1000 Islands

1000 Islands NY tour St. Lawrence River

  • Welcome
  • Visiting
    • Plan Your Visit
    • Rules Of Boldt Facilities
    • Hospitality
    • Photography
  • Virtual Tour
    • Download the Boldt Castle App
    • The Alster Tower
    • The Castle
    • The Castle Interior
    • The Dove-Cote
    • The Entry Arch
    • The Gardens & Grounds
    • The Gazebo
    • The Power House
    • Renovations
    • Kestrel 1892 Steam Yacht
  • Weddings
  • History
  • News & Events
    • Independence Day Fireworks
    • Economic Impact in Region
  • Yacht House
  • Downloads
    • Download the Boldt Castle App
    • Literature
    • Photo Gallery
    • Videos
    • Wallpapers
  • Employment

The Alster Tower

The Alster Tower is often referred to as the Playhouse.

Completed in 1899, the Alster Tower is the most architecturally unique structure on Heart Island. With a two-lane bowling alley, Kitchen, Billiard Room, Venetian Room, Library, Shell-Room and Theater, George Boldt wanted to create the ideal atmosphere for recreational activities. Unlike the main Castle, the Boldt family actually used the tower up until the time of Louise’s death in 1904.

It is likely that this structure may have actually been modeled off of a temporary tower built in the Alster River Basin in Hamburg, Germany in 1895 for Kaiser Wilhelm’s celebratory grand opening of the Kiel Canal.

The tower was constructed out of red-sandstone, locally quarried somewhere along the river bank.

After several years of stabilization, the Thousand Islands Bridge Authority opened the Alster Tower again to the public in 2014; complete with protective sea walls, new windows, total masonry re-pointing, roofing and landscaping.

2025 Dates & Hours of Operation:

    Boldt Castle & Boldt Yacht House

    • May 10 - October 13:

      10:30 AM - 6:30 PM

    • Admissions Booth closes 1 hour prior to Boldt Castle closing.

    Special Hours:

    Boldt Castle and Yacht House will remain open until 7:30pm on Independence Day Weekend on Friday, July 4th and Saturday, July 5th.

    For more info: 315.482.9724

    Boat tours from both the U.S. and Canada stop at Heart Island. Extensive docking is available for private pleasure craft. A shuttle from Heart Island provides access to the Boldt Castle Yacht House.

    Please Note: The Castle does not have climate control. Please dress appropriately for the weather.

    **We accept major credit cards and US cash.**

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Web site courtesy of the:
Thousand Islands Bridge Authority / Boldt Castle
PO Box 428, Collins Landing
Alexandria Bay, NY 13607

In Season: 315-482-9724
Off Season: 315-482-2501

Coordinates:
+44° 20' 40.29" N, -75° 55' 21.27" W

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