Tasiujaq, formerly known as Eclipse Sound, is a large saltwater sound in Nunavut's Qikiqtaaluk Region, separating Bylot Island to the north from Baffin Island to the south. It connects to Baffin Bay via Pond Inlet to the east and to Navy Board Inlet to the northwest. The primary and likely only practical access point for paddlers is the community of Pond Inlet, located on the southern shore of the sound. Described as a remote hamlet on the northern tip of Baffin Island, it is accessible by air and provides a launch from a pebble beach. The sound is characterized by its deep indigo and meridian blue waters, which are often filled with a maze of fantastically shaped ice chunks and towering, glittering icebergs, being 30 stories high. The surrounding scenery includes the snowy mountains and glaciers of Bylot Island, which is a wildlife reserve. The paddling experience is defined by profound solitude, silence, and dramatic Arctic beauty, with the midnight sun providing extended daylight during the summer season.

The viable paddling season is extremely short, confined to the brief Arctic summer which lasts barely six weeks from July through August. During this period, air temperatures can reach a balmy 45 degrees Fahrenheit, and daylight stretches to 20 hours. The sound is a critical summer habitat for narwhals, though their numbers have declined dramatically. Paddlers share these waters with increasing vessel traffic; between 2015 and 2019, transits through the eastern entrance of the sound increased by 384 percent, with most related to mining and some to tourism. Cruise operators have, however, agreed to avoid this specific waterway. The presence of large ships and the potential for ice, both in the form of bergs and seasonal pack ice, are significant hazards. The sound's exposure to Baffin Bay means it is subject to open ocean conditions, including wind, fetch, and sea ice dynamics monitored by research cameras. There are no settlements within the sound itself apart from Pond Inlet. Paddlers must be entirely self-sufficient, prepared for cold water immersion, and aware that this is a culturally significant subsistence area for Inuit hunters from Pond Inlet.