Boldt Castle
Alexandria Bay, NY
An unfinished six-story castle on Heart Island, begun by a hotel magnate for his wife. Reached by tour boats or water taxi from Alexandria Bay; bring a passport if your cruise enters Canada.
- Nearest town
- Alexandria Bay, NY
- Category
- History & culture
- GPS
- 44.3446, -75.9224
- Editor's pick
- ★
Hours, fees and access change. Confirm with the operator or park before you go.
Good to know
Best time to go
The most pleasant months are usually June and August–September. Still fine, with some compromises, in May and July. Cold, short days in November–March. (Estimate from long-term temperature averages, terrain and pass seasons)
Featured in these trip guides
Nearby
Campsites nearby
- Keewaydin State Park CampgroundCampsite1 mi from Boldt Castle · 48 pitchesTentsCaravans
- Santway ParkCampsite11 mi from Boldt Castle · 5 pitchesFree
- Jacques Cartier State Park CampgroundCampsite19 mi from Boldt Castle · 35 pitchesTentsCaravans
- Bird's Nest CampgroundMotorhome stopover19 mi from Boldt CastleMotorhomes
- Love's RV HookupMotorhome stopover24 mi from Boldt Castle · 5 pitchesMotorhomes
- Black River Bay CampgroundsMotorhome stopover24 mi from Boldt CastleMotorhomes
All campsites in New York · Campsite data: © OpenStreetMap contributors, ODbL 1.0 · Updated October 3, 2026
FAQs
Where is Boldt Castle?
Boldt Castle is in Alexandria Bay, NY, at GPS 44.3446, -75.9224. It is about 10 mi from Mallorytown.
Can you camp near Boldt Castle?
Yes. The nearest campsite listed in OpenStreetMap is Keewaydin State Park Campground, about 1 mi away; within 25 mi there are 9 campsites and motorhome stopovers.
Which road trips pass Boldt Castle?
Boldt Castle is a stop on these CampingSpirit trip guides: Lake Ontario and the Thousand Islands.
What is there to see near Boldt Castle?
Places worth a stop nearby: Wellesley Island State Park (5 mi), Tibbetts Point Lighthouse (28 mi), Fort Ontario (67 mi) and The Wild Center (74 mi).
When is the best time to visit Boldt Castle?
The most pleasant months are usually June and August–September. Still fine, with some compromises, in May and July. (Estimate from long-term temperature averages, terrain and pass seasons)