Once a year, the Canadian Museum of Nature opens its Natural Heritage Campus to the public for a day, offering a rare glimpse at the work that goes on behind the scenes at a museum.

Located in Gatineau, Que., the facility covers an area the size of five regulation ice hockey rinks and houses some 14 million specimens and historic artifacts, including fossils, minerals, insects, plants, and even artworks and rare books, as well as several research labs.

The annual open house is a way to broaden the public’s understanding of what a national museum does, explains Dan Smythe, senior media relations officer for the Museum of Nature.

“We have our public face in downtown Ottawa, with fantastic exhibitions and public programs, but we’re also a national research and scientific institution,” he says. “We’re visited by hundreds of other researchers and graduate students from around the world every year, and thousands of the specimens that are here go out on loan to other research institutions. The open house really shows the diversity and the scope of what we mean when we talk about natural history across Canada and around the world.”

Canadian Geographic got a sneak peek at this year’s open house, which takes place Saturday, Oct. 15, and challenged several curators and research scientists to share their favourite specimen from among the museum’s vast collections.

Kieran Shepherd, Curator, Paleobiology

“I love fossils from the Arctic, because they tell such a rich and fabulous story. This rubble is from one of my favourite mammals, Coryphodon, a hippo-like mammal that lived 53 million years ago all over the world, including in our Canadian Arctic when it was warm and tropical. It’s kind of sad; Coryphodon had the smallest body to brain ratio of any mammal that’s ever existed. It weighed 500 kilograms and its brain was 90 grams — that’s like a couple of chunks of cheese put together.”