Nature and science

Fathom Five National Marine Park

Dolomite, 420 million years old, rises through the sparkling waters of Lake Huron to form Fathom Five National Marine Park. This is a freshwater ecosystem of ancient rock formations, cliff-edge forests, fascinating dive sites on 22 shipwrecks, and orchid species both plentiful and rare. Visit for a day or backcountry camp on starry-skied Flowerpot Island—Fathom Five is equal parts mystery and recreation, ecology and culture—and a welcoming escape to nature


Featuring both ancient geological wonders and a vital cultural legacy, Fathom Five National Marine Park reaches out from Ontario’s Bruce Peninsula to protect a lush archipelago and a surrounding freshwater ecosystem.

Discover unique features


Our peninsula is unique in Canada for the wide variety of wildflowers that live here.

This is because for a relatively small bit of land, the Bruce has an unusually rich diversity of habitats, from the rugged cliffs of the Niagara Escarpment, to flat, dry rock plains called alvars, to various types of swampy wetlands.

© Parks Canada

One of our chief claims to fame is the profusion of species of orchids found here. Orchids are not just tropical plants. There are, believe it or not, more than sixty species in Ontario. Approximately 43 are found on the Bruce Peninsula, likely due to the area’s variety of habitats. They are picky plants that often grow along with specific fungi, making orchids almost impossible to transplant. The plant uses the fungus to obtain nutrients and vice versa in a symbiotic relationship.

From mid-May to early June, Flowerpot Island in Fathom Five National Marine Park is the place to go to see the wonderful calypso orchid. A small number of these small, delicate beauties bloom along the island's trails. Also known as fairy slipper, this orchid grows from coast to coast across northern Canada.

If you go out to have a look, remember that many others come to see these flowers every year. Large numbers of people leaving the paths to get a better look or take pictures have caused the destruction of about one-third of the calypsos that were visible from the trails ten years ago, so please view them from the trail!

One of the most unusual of our orchids is the Alaskan rein orchid, which, as its name suggests, is native to Alaska and northwest Canada. The only other places it's found are Anticosti Island in the Gulf of St. Lawrence, and here on the peninsula.

Orchids aren't the only unusual plants on the Bruce. We are also home to about half of the world's dwarf lake iris, and most of Canada's stock of Indian plantain. The peninsula is also home to more than twenty kinds of fern, including the rare northern holly fern. A reminder: it is illegal to remove anything from a national park

About park fauna

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