right|thumb|Detail of a span from the bridge deck
The Caledonia Bridge, also known as the Grand River Bridge (built 1927) is a road bridge located in Caledonia, Ontario, Canada on Argyle Street. The bridge is the only nine-span bridge of its kind in Canada and is considered the first reinforced concrete bridge of its type ever built.
The bridge is on the Ontario Heritage Bridge List and is designated by the Haldimand County LACAC (Local Architectural Conservation Advisory Committee).
The bridge is scheduled to be replaced by a new bridge due to structural damage and age. A number of bridge deficiencies were found requiring action. The condition included structural deficiencies, structural deterioration, insufficient roadside safety, foundation problems and inadequate hydraulics. The engineering consulting firm Morrison Hershfield was approached to conduct a Context Sensitive Design Workshop for the bridge. They involved stakeholders and representatives from the public to participate in the bridge design to address various environmental aspects of the project. Completion of the bridge was tentatively scheduled for 2012, but as of 2024, minimal work has been done towards its replacement.
History
Before the construction of the first bridge, a series of ferries were arranged to transport people from the North to the South and vice versa. On March 6 of 1834, the proposal of a plank wood road stretching from Hamilton to Port Dover succeeded. The Hager brothers were brought into the area for construction of the original bridge, construction a wooden bridge with a swing section in 1842 and completing the project in 1843. This resulted in the building of two Caledonia landmarks; Haldimand House: A Stagecoach-Inn, and the first Caledonia Bridge. This first bridge was wooden, with no pedestrian sidewalk, with wooden walls on either side for protection.
Caledonia's Grand River Sachem reported the collapse of this bridge in 1861, stating that the "Spring Freshet" took out the bridge, damaged the Caledonia Dam and wiped away most of the Seneca Bridge. Two temporary bridges were constructed between 1861 and 1874. Many people returned to the ferrying system or even resorted to rowboats to cross the river during the 4 years it took to complete construction on the temporary bridge. The last temporary bridge was replaced by a new, state of the art, 5 span iron bridge in 1875 designed by Mr. A.J. Brown. The iron being formed at Scott's Foundry located on the eastern corner of Edinburgh Square and Caithness Street. The iron bridge had a wooden floor, a wooden wall on one side and one sidewalk, the wood being cut at Ranald McKinnon's sawmill. A toll house was also constructed on the north side of the bridge, to pay off the more than $22,000.00 debt the town had incurred building the bridge. During the 1900's, the town also ran power, gas and phone lines under the bridge. This bridge lasted until 1925 when a truck carrying a load of stone collapsed an entire span. A group of children were swimming underneath the bridge when the incident took place and the truck driver personally saved the lives of five or more children.