Thousand Islands National Park National Park

Archipelago national park protecting St. Lawrence islands

An archipelago in the St. Lawrence River offering boating, kayaking, camping and island-hopping among granite islands; visitors come for freshwater scenery and outdoor recreation.

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Thousand Islands National Park at a Glance#

Address: Thousand Islands National Park, Ontario, Canada (park span across St. Lawrence River islands near Kingston and Brockville)

Website: https://www.pc.gc.ca/en/pn-np/on/1000

Hours: Park visitor services seasonal (typically May-Oct); parks open year-round for viewing

Admission: Park entrance/registration fees apply for some services; basic island access varies (Parks Canada fees may apply for boat launch/visitor services)

About Thousand Islands National Park#

Thousand Islands National Park is a protected area of islands, shorelines and mainland parcels on the St. Lawrence River in Ontario, Canada; it was first established in 1904. The park conserves riverine islands and shoreline habitat within the Thousand Islands region and serves both recreation and conservation roles.

The park is best known for its mosaic of islands and river channels that are explored by boat. Visitors use marked mainland trails, picnic areas and campgrounds and take boat or kayak trips to reach small, wooded islands and shoreline viewpoints. Mallorytown Landing is the main visitor hub with facilities for day visitors, campers and boat access into the island network.

The park was created in 1904 as St. Lawrence Islands National Park and later renamed; it has been managed to protect fragile island ecosystems while accommodating low-impact recreation. Facilities and access arrangements have evolved to concentrate visitor services on a few mainland sites and to limit development on islands.

The park lies on the St. Lawrence River in eastern Ontario between the urban centres along the river corridor, with mainland access points near small river towns and boat launch sites. Many park units are island parcels in the river channel rather than a single contiguous landmass.

  • Boat access: Many islands are reachable only by private boat or park boat tours, so bring or arrange water transport for exploring beyond mainland sites.
  • Best time to visit: Peak visitor season runs from late spring through early autumn when camping, kayaking and swimming are available.

What to See#

  • Mallorytown Landing: Serves as the park’s main mainland access point with a visitor centre, campground and day-use facilities that act as the base for boat trips into the island clusters.

How to Get to Thousand Islands National Park#

The park comprises many islands along the St. Lawrence between Kingston and Brockville. Access is primarily by private boat or commercial boat tours departing from Kingston, Gananoque and Brockville; local marinas offer boat rentals and launch services.

Tips for Visiting Thousand Islands National Park#

  • If arriving by private boat, check local mooring rules and protected-areas regs; many islands are fragile.
  • Book camping or lodge permits in advance in summer; prime weekend slots fill quickly.
  • Fishers and kayakers should watch for rapidly changing winds across the St. Lawrence; mornings are usually calmer.

Best Time to Visit Thousand Islands National Park#

Best summer for recreational boating and camping; autumn for quiet paddling and foliage.

Summer (Jun-Aug)
June-August · 18-28°C
Peak season for boating, island camping and swimming; warm water and busy facilities.
Autumn (Sep-Oct)
September-October · 5-15°C
Brisk air and vivid foliage; quieter island campsites and good paddling weather early in the month.
Late Spring (May)
May · 10-18°C
Cooler waters but fewer crowds and strong migratory birdwatching.

Weather & Climate near Thousand Islands National Park#

Climate

Thousand Islands National Park's climate is classified as Warm-Summer Continental - Warm-Summer Continental climate with warm summers (peaking in July) and freezing winters (coldest in January). Temperatures range from -13°C to 26°C. Moderate rainfall (969 mm/year).

Air Quality: AQI 23 Good
Best Time to Visit
JulyAugustJune
Temperature & Rainfall
Temperature Range
36°
Warmest Month
-31°
Coldest Month
Monthly Conditions
Month Comfort Temp Feels Rain Sky Humidity Wind UV Daylight
January Poor -13° - -3° -14° 72 mm overcast 89% 4.3 m/s 0.1 low 9.1h
February Poor -12° - -2° -13° 62 mm overcast 88% 4.1 m/s 0.3 low 10.3h
March Poor -6° - 3° -6° 61 mm partly cloudy 79% 4.2 m/s 0.6 moderate 11.8h
April Acceptable 1° - 10° 2° 75 mm partly cloudy 75% 4.2 m/s 1.0 moderate 13.3h
May Good 7° - 18° 12° 80 mm partly cloudy 75% 3.6 m/s 1.4 high 14.6h
June Very Good 12° - 23° 17° 81 mm partly cloudy 75% 3.2 m/s 1.6 very high 15.3h
July Excellent 15° - 26° 21° 76 mm partly cloudy 72% 3.1 m/s 1.7 very high 15.0h
August Excellent 15° - 25° 20° 92 mm partly cloudy 71% 3.0 m/s 1.4 high 13.8h
September Very Good 11° - 20° 15° 105 mm partly cloudy 72% 3.3 m/s 1.0 high 12.4h
October Acceptable 5° - 14° 7° 85 mm overcast 77% 3.8 m/s 0.5 low 10.8h
November Poor 0° - 7° 0° 99 mm overcast 81% 4.3 m/s 0.2 low 9.5h
December Poor -8° - 1° -9° 81 mm overcast 86% 4.4 m/s 0.1 low 8.7h

Nearby Attractions to Thousand Islands National Park#