The five-span stone bridge in Pakenham, Ontario is an outstanding example of a long, stone arch bridge in Canada and a highly significant heritage bridge. It crosses the Mississippi River (Canada's Mississippi, not the famous U.S. river) in the town of Pakenham, now part of Mississippi Mills, Ontario, Canada. Pakenham is located less than 50 km (30 miles) West of Ottawa.
Built in 1901 or 1903, depending on the source, it replaced older wooden bridges that were often damaged by spring ice. For the princely sum of $13,000 plus $2,400 for a temporary bridge, it took 9 weeks to build from locally quarried stone, employing 70 men.
The bridge is 82 m (268 feet) long, 6.7 m (22 feet) high, and 7.6 m (25 feet) wide. Each arch is approximately 12 m (40 feet) wide. The largest stone in the bridge weighs over 5 tons. It is often repeated that this is the only bridge of its kind in North America, however it is not the only five-span stone bridge.
Not only is the bridge beautiful, but its location is in a beautiful part of the Mississippi Valley.
There is a small picnic area for the observers that are attracted to this unique structure and picnic tables along the river near beautiful wildflowers.
It is fascinating that the bridge underwent an extensive rehabilitation in 1984 to widen the road, reinforce the bridge's structure and add wing walls. During this process, each stone was removed, documented and later replaced in the same precise location. The supplementary load bearing concrete structure is completely hidden so the only visible difference is the wider road.
Below, one of a group of old nails embedded in the limestone nearby.
References
Ontario: Pakenham Bridge
Pakenham Bridge
Images
Photos from the iPad of 
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