Shadowy figures moved beneath the 15 cm of ice covering Lake Weissensee in Austria this month, wielding sticks and surfacing periodically for air.
A few brave divers have flipped Canada's favourite sport upside-down — and taken it underwater. Reuters photographer Michael Dalder was there in mid-February to capture the highlights of the Underwater Ice Hockey Championships.
Dalder documented the trip, during which he dove with the daredevil hockey players on his blog.
He says the hockey players on each team are apnea divers, who plunge deep into waters while holding their breath. Since that wasn't difficult enough, apparently, now they compete for goals in upside-down nets, using a foam puck floating on the underside of an ice-covered lake.
There is no risk of skate blades cutting anyone in this game. Still, Dalder writes that ice diving is considered one of the most dangerous varieties because swimmers must reach one of the entrance and exit holes cut into the ice to breathe.
Canada has clubs for underwater hockey, played at the bottom of a pool with a sinking puck. But that sport doesn't require diving into icy cold lakes in the middle of winter.
So far there's no sign of Canadians putting down the Tim Hortons coffees and diving into their ice fishing holes.