Stretch of Lake Huron shore was promised to Saugeens in 1854 treaty with Crown but wrongly omitted from map

A stretch of beach will be returned to a First Nation in Canada 170 years after it was mistakenly omitted from its reserve. The sandy sliver of land measures less than two miles long, but has nonetheless sparked an outsized battle, with a nearby resort town claiming the case sets a foreboding precedent for property rights in the country.

Canada’s supreme court said on Thursday that it would not hear a challenge from the town of South Bruce Peninsula, which is contesting a lower court’s ruling that the Saugeen First Nation’s reserve was erroneously smaller than promised.

In its application to the country’s highest court, the town warned that a victory for the Saugeens would “risk sowing uncertainty and unpredictability at the core of Canada’s system of private landholding”. Lawyers for the First Nation instead said the case was simply about the correct interpretation of a treaty – and the boundaries of the First Nations reserve under that agreement.

Central to the fight is stretch of beach 140km from Toronto, popular with tourists the summer months who trek 140 miles from Toronto to enjoy pristine blue waters of Lake Huron.