Wood Buffalo National Park

Under the park are rocks that slowly dissolve in water. That makes holes in the ground and salty streams.

Three big rivers flow through the park.

Most of the park is a flat, poorly drained plain. Parks Canada says it sits on old layers of rock such as gypsum, salt, dolomite and limestone. Water soaks down through these rocks and dissolves them, making sinkholes, underground streams, salty streams and salt flats.

The Athabasca, Peace and Slave rivers flow through the park. The Peace-Athabasca Delta is one of the largest inland freshwater deltas in the world.

The Northern Boreal Plains, which cover most of the park, are flat and poorly drained, 210-300 m above sea level, on Devonian sedimentary bedrock (gypsum, halites, dolomite, limestone) under glacial deposits. Uniform relief, porosity and solubility make drainage mainly vertical: percolating water has created karst in gypsum areas, salt flats, underground streams, sinkholes and saline streams (Parks Canada).

The Athabasca, Peace and Slave rivers and the biologically productive Peace-Athabasca Delta, one of the largest inland freshwater deltas in the world, are the main topographic features.

Wood bison, wolves and whooping cranes live in this park.

Whooping cranes come here to raise their chicks.

UNESCO says the park sustains the world's largest herd of wood bison, a threatened animal. It is the only place where wolves and wood bison have kept their hunter-and-hunted relationship going, unbroken, over time.

The park also has the only breeding grounds in the world for the endangered whooping crane, in marshes, ponds and bogs in its remote north. Birds from all four North American flyways pass through the Peace-Athabasca Delta in spring and fall.

The park sustains the world's largest herd of wood bison, a threatened species, and is the only place where the wolf-wood bison predator-prey relationship has continued unbroken (UNESCO). Its boreal forest of white and black spruce, jack pine, balsam fir, aspen and poplar is shaped by fire, a natural force there (Parks Canada).

The only breeding habitat of the endangered whooping crane lies in a fragile complex of marshes, ponds, lakes, streams and bogs in the north-central corner; it and the Peace-Athabasca Delta became Ramsar sites, the delta a major nesting and staging area used by waterfowl from all four North American flyways (Parks Canada).

At night, the sky over the park is very dark, so you can see lots of stars.

Sometimes the northern lights glow in the sky here.

On 28 June 2013, the Royal Astronomical Society of Canada named Wood Buffalo National Park a Dark-Sky Preserve, working with Parks Canada. The society says it is the largest designated dark-sky site in the world.

The park sits under the auroral oval, so even small disturbances in the Earth's magnetic field can bring the northern lights. Pine Lake campground has an open-air deck for stargazing.

The Royal Astronomical Society of Canada (RASC) designated the park a Dark-Sky Preserve on 28 June 2013 in partnership with Parks Canada, calling it the world's largest designated Dark-Sky Site; the core area's night-sky quality is about 21.65 mag/arcsec2 (RASC).

Because the park lies along the Earth's auroral oval, even modest geomagnetic activity produces the aurora borealis. Pine Lake campground, with its open-air Dark Sky Circle, is the main observing site; the park and a Fort Smith astronomy society host an annual Dark Sky Festival, usually in the third week of August (RASC).

Bison are big and strong. Always watch them from far away.

Cover your arms and legs to stop mosquito bites.

PlayOwl's advice: watch bison and other wild animals from a long way off, and never walk up to them. The park is remote: the RASC says the town of Fort Smith is 60 kilometers north of Pine Lake campground, and many visitors fly there.

Mosquitoes can spread germs that make people sick. The CDC says to use insect repellent and wear loose, long-sleeved shirts and long pants, because mosquitoes bite day and night.

PlayOwl's advice: keep a wide distance from bison and other large wildlife, and follow park staff instructions.

CDC mosquito guidance: EPA-registered repellents, loose-fitting long sleeves and pants; mosquitoes bite day and night and can spread germs that cause illness.