[1] Aerial photographs taken from 1949 to 2018 indicate the shaft was covered by snow year-round, and may have only became noticeable in recent decades in the summer melt season due to glacial retreat.

[2] In the spring of 2018, a Canadian government team was surveying caribou populations by helicopter when the pilot, Ken Lancour, spotted a deep, snow-filled depression at the cave entrance.

[1][4][5] In September 2018, a team led by geologist Catherine Hickson and archaeological surveyor John Pollack returned to the site and made a partial descent into the cave once it was snow-free, estimating it to be at least two kilometres (1.2 mi) long.

[1][3] In British Columbia (BC), comparable caves would include Devil's Bath–a 100 to 120 m (330 to 390 ft) diameter water-filled sink—and Vanishing River, both on northern Vancouver Island.

[2] The Northwest Territories (NWT) has several large karst features including the Vermillion Creek Collapse (120 m by 60 m wide by 40 m deep).