📷 Photo by Nikhil Mitra on UnsplashLake Ontario and the Thousand Islands
Along the Seaway Trail from Oswego to castles on islands in the St. Lawrence River.
- Distance
- 228 km (142 mi)
- Driving
- 2 h 32 min
- Suggested days
- 3
- Stops
- 8
- States
- NY
- Updated
- April 29, 2026
At a glance: 3-day road trip of about 228 km (142 mi) with 8 stops, from Syracuse to Boldt Castle. About 2 h 32 min of driving in total.
More road trips in New York
Route description
Leave Syracuse north on State Road 481 to Oswego and Fort Ontario, a star fort on the lakeshore. From here the Great Lakes Seaway Trail follows State Road 3 along Lake Ontario, past dunes and state parks, to Sackets Harbor, a War of 1812 battlefield and naval base with a charming village.
Continue on State Road 12E to Cape Vincent and Tibbetts Point Lighthouse, where Lake Ontario becomes the St. Lawrence River. This is a wonderful sunset spot, and freighters glide past on the Seaway.
Follow the river to Clayton, a boating town with the Antique Boat Museum, then cross the Thousand Islands Bridge to Wellesley Island State Park for river campsites and trails.
Finish at Alexandria Bay, where tour boats leave for Boldt Castle on Heart Island and cruises among the islands. Some cruises enter Canadian waters, so bring a passport. The season runs from May to mid-October.
Stop-by-stop itinerary
In driving order. Distances are estimates between consecutive stops.
- 1Start
Syracuse
NY - 266 km
Fort Ontario
HistoryOswego, NYA star-shaped fort above Lake Ontario that later sheltered nearly 1,000 World War II refugees, told at the nearby Safe Haven museum.
- 374 km
Sackets Harbor
NY - 432 km
Tibbetts Point Lighthouse
ViewsCape Vincent, NYA white lighthouse where Lake Ontario flows into the St. Lawrence River; a great sunset spot and a good place to watch ships.
- 533 km
Clayton
NY - 612 km
Wellesley Island State Park
NatureFineview, NYA large island park reached by the Thousand Islands Bridge, with river campsites and a nature center with trails over granite knobs.
- 710 km
Alexandria Bay
NY - 81 km
Boldt Castle
HistoryAlexandria Bay, NYAn 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.
Suggested stages and overnight stops
3 days, split by driving time. Campsites from OpenStreetMap: check opening dates before you go.
- Day 1: Syracuse → Fort Ontario · 41 mi · 0 h 44 minOvernight nearby, for example: Brennan Beach Campground (18 mi); Chipmunk Loop (16 mi).
- Day 2: Fort Ontario → Sackets Harbor · 46 mi · 0 h 49 minOvernight nearby, for example: Love's RV Hookup (11 mi); Willows on the Lake (4 mi).
- Day 3: Sackets Harbor → Boldt Castle · 55 mi · 0 h 59 minOn the way: Tibbetts Point Lighthouse, Clayton, Wellesley Island State Park, Alexandria Bay.Overnight nearby, for example: Keewaydin State Park Campground (1 mi); Swan Bay Resort (4 mi).
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. July and August are the busiest months: book campsites early.
Estimate from long-term temperature averages, terrain and pass seasons
FAQs
How long is Lake Ontario and the Thousand Islands?
3-day road trip of about 228 km (142 mi) with 8 stops, from Syracuse to Boldt Castle. About 2 h 32 min of driving in total.
How many days do you need for Lake Ontario and the Thousand Islands?
We suggest 3 days: about 2 h 32 min of driving, which leaves time for the stops.
Where does Lake Ontario and the Thousand Islands start and end?
It starts in Syracuse and ends in Boldt Castle.
Which states does Lake Ontario and the Thousand Islands pass through?
New York.
Where can you camp along Lake Ontario and the Thousand Islands?
OpenStreetMap lists 19 campsites and motorhome stopovers within 19 mi of the stops on this route. For example: Pine Woods Camping Area, Onieda Shores Park Campground and Keewaydin State Park Campground.
When is the best time for Lake Ontario and the Thousand Islands?
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)
