Porphyry Island Provincial Park is a 106.84 hectare nature reserve at the southern end of the Black Bay Peninsula in Lake Superior, east of Sleeping Giant Provincial Park. Ontario Parks lists the park as established in 1968.
The island is the last in a chain stretching southwest from the Black Bay Peninsula. It is generally flat to rolling, with little relief and a rugged shoreline that offers little shelter.
Porphyry Island is a specialized page for Lake Superior island geology and plant conservation. Ontario Parks says the rocks of the peninsula and island are Late Precambrian and include more than 300 distinctive lava flows, typically grey-green basalt with minor sedimentary rocks. Geologists call these rocks the Osler Group.
The reserve takes its name from quartz and feldspar crystals, or porphyries, in the volcanic rocks. The interior supports mixed forest, wetlands with black spruce, lichens on mature trees and rocky shorelines, arctic species, and devil's club. Ontario Parks notes that devil's club populations here and on adjacent islands are the only known occurrences east of the Rocky Mountains.
There are no visitor facilities, the remote island location makes visitation difficult, unauthorized collection is prohibited, and scientific research requires an approved application.
Plan around geology research, remote Lake Superior island context, rare plant awareness, shoreline observation, map review, and low-impact photography where access is appropriate.
Confirm access, maps, no-facility expectations, collection prohibitions, research application requirements, Lake Superior conditions, weather, alerts, and park rules through Ontario Parks.
Non-operating park in Ontario Parks locator.
