The Rideau Canal is Ottawa’s defining landmark—a 202-kilometre waterway that shaped the city’s history and remains one of North America’s most remarkable engineering achievements. From its military origins to its status as the world’s largest skating rink, the canal tells the story of Canadian ingenuity and perseverance.
Designated a UNESCO World Heritage Site in 2007, the Rideau Canal stands as the best-preserved example of a slack-water canal in North America and the only canal from the great canal-building era still operating along its original line with most original structures intact.
Key Highlights
TL;DR: The Rideau Canal was built 1826-1832 as a military supply route, connecting Ottawa to Kingston via 202 km of waterway, 47 locks, and 24 lock stations. Now a UNESCO World Heritage Site, it transforms into the world’s largest skating rink each winter.
| Quick Facts | Details |
|---|---|
| 📅 Built | 1826-1832 |
| 📍 Length | 202 km (125 miles) |
| 🎟️ Status | UNESCO World Heritage Site |
| ⏰ Locks | 47 locks at 24 stations |
Why the Canal Was Built
The War of 1812 Threat
The Rideau Canal owes its existence to military necessity. During the War of 1812, the vulnerability of the St. Lawrence River—Canada’s main supply route—became dangerously clear:
- The St. Lawrence ran along the American border
- American forces could easily disrupt shipping
- British troops needed a secure inland route
- Supply lines were essential for defending Canada
The Solution
British military planners decided to build an alternative route:
- Connect the Ottawa River to Lake Ontario
- Use existing rivers and lakes where possible
- Build locks to navigate elevation changes
- Create a secure military corridor inland from the border
In 1826, Lieutenant-Colonel John By arrived to make this vision reality.
Illustrative image only.
Building the Canal
The Construction Challenge
Colonel By faced an enormous task:
Terrain Challenges:
- Dense wilderness with no roads
- Rocky Canadian Shield outcrops
- Swamps and wetlands
- Dramatic elevation changes
- Harsh winters limiting work seasons
The Route:
- Start at the Ottawa River (Bytown)
- Follow the Rideau River south
- Cross the height of land
- Connect to the Cataraqui River
- End at Kingston on Lake Ontario
The Workforce
Thousands of workers built the canal:
- Irish immigrants (largest group)
- French-Canadian labourers
- Scottish stonemasons
- English craftsmen
- Indigenous workers
The Human Cost
Construction claimed many lives:
- Malaria (“swamp fever”) was the biggest killer
- Hundreds died from disease
- Workplace accidents were common
- Harsh conditions caused suffering
- Many unmarked graves line the route
Despite the hardship, the workers completed an engineering masterpiece in just six years.
Engineering Achievements
The Lock System
The canal’s 47 locks at 24 stations remain marvels of engineering:
Ottawa Locks:
- Eight locks descend 24 metres
- Still operated by hand
- Located beside Parliament Hill
- Most photographed section
Jones Falls:
- Highest dam in North America when built
- Stone arch dam rises 19 metres
- Included a unique “overflow dam”
- Engineering innovation of its era
Newboro:
- Summit level of the canal
- Where water divides north and south
- Critical control point
Construction Techniques
By’s methods were advanced for the time:
- Hydraulic lime mortar for waterproof construction
- Cofferdam techniques for underwater work
- Stone arch construction for permanence
- Integrated watershed management
Why It Still Works
The canal operates with original infrastructure because:
- High-quality stone construction
- Overbuilt for military specifications
- Careful maintenance over generations
- Design that accommodates natural water flow
The Canal Today
Navigation
The Rideau Canal remains fully navigable:
Boating Season:
- Opens mid-May to mid-October
- Transit takes 3-5 days
- Pleasure boats, kayaks, canoes welcome
- Lock passage is free (as of recent years)
Lock Operations:
- Parks Canada staff operate locks
- Most locks still hand-cranked
- Operating hours vary by season
- Historic experience of canal travel
The Skateway
Each winter, 7.8 kilometres of the canal through Ottawa transform into the Rideau Canal Skateway:
- World’s largest naturally frozen skating rink
- Equivalent to 90 Olympic hockey rinks
- Free to skate
- Features warming huts and concessions
- BeaverTails and hot chocolate tradition
- Heart of Winterlude festival
Skateway Facts:
- Opens when ice reaches safe thickness
- Typically January through March
- Weather dependent each year
- Attracts over 1 million skaters annually
Illustrative image only.
UNESCO World Heritage Status
The Designation
In 2007, the Rideau Canal was inscribed as a UNESCO World Heritage Site:
Criteria Met:
- Outstanding example of a technological ensemble
- Represents a significant stage in human history
- Directly associated with events of outstanding significance
What’s Protected:
- The entire 202-kilometre waterway
- All 47 locks and related structures
- Historic buildings and landscapes
- The engineering heritage
International Recognition
The Rideau Canal stands alongside sites like:
- The Pyramids of Egypt
- The Great Wall of China
- The Taj Mahal
- The Canadian Rocky Mountain Parks
This recognition ensures its preservation for future generations.
Exploring the Canal
Ottawa Highlights
Within Ottawa, the canal offers:
Parliament Hill Locks:
- Eight-lock flight beside Parliament
- Dramatic entrance from Ottawa River
- Ottawa Locks Visitor Centre
- Best viewing from nearby bridges
Dow’s Lake:
- Pavilion with boat rentals
- Scenic parkland
- Tulip festival displays
- Year-round recreation
Hog’s Back Falls:
- Dramatic waterfall section
- Popular park area
- Historic lock station
- Swimming and fishing nearby
Beyond Ottawa
The full canal route passes through:
- Historic villages (Merrickville, Westport)
- Provincial parks
- Lakes perfect for boating
- Heritage lock stations
- Rural Ontario countryside
Frequently Asked Questions
Q: Can I still boat through the canal? A: Yes! The canal is fully operational for boats from mid-May to mid-October. Contact Parks Canada for current schedules and any fees.
Q: When was the Skateway started? A: The Rideau Canal Skateway was first cleared in the winter of 1970-71 and has operated most winters since.
Q: Why is the canal called “Rideau”? A: French explorer Samuel de Champlain named the waterfall at the canal’s entrance “Rideau” (curtain) because it reminded him of a curtain. The name was applied to the river and later the canal.
Q: Has the canal ever been used militarily? A: No. By the time construction finished in 1832, relations with the United States had improved, and the canal was never needed for its military purpose. It immediately became a commercial route instead.
Q: How deep is the canal? A: The canal maintains a minimum depth of about 1.5 metres (5 feet), sufficient for pleasure craft and smaller vessels.
Final Thoughts
The Rideau Canal represents the best of human ambition and engineering skill. Built in six years through wilderness, it has served Canadians for nearly 200 years—far longer than its builders imagined possible.
Today, whether you’re boating its full length in summer, skating past Parliament Hill in winter, or simply walking its scenic pathways, you’re experiencing a living piece of history. The canal that was built for war has become a symbol of peace and recreation—a UNESCO treasure at the heart of Canada’s capital.
The workers who built it would be amazed to see millions of people skating where they once laboured. Colonel By would be proud that his engineering masterpiece still functions perfectly. And Ottawa exists because of this remarkable waterway that cuts through its heart.
Source: Parks Canada, UNESCO, Historical Society of Ottawa - Compiled for Via Ottawa readers.
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