Port Sandfield is a community on Lake Rosseau in Ontario, Canada, located within and governed by the municipality of Muskoka Lakes. It was founded in 1870, when a canal was built connecting Lake Joseph to Lake Rosseau. Alexander Peter Cockburn, a member of the Ontario Provincial Parliament and founder and first President of the Muskoka Settlers’ Association played a leading role in getting the canal funded. The canal was funded at the same time as a lock at Port Carling. The canal and lock allowed a fleet of steamboats to carry freight, mail, cargo and timber over the three largest lakes in the county of Muskoka.