MacAlpine Lake is a large lake located in the Keewatin region of Nunavut, Canada, situated in a tundra landscape approximately 140 km south of the Arctic Ocean. The lake lies nearly 400 km northwest of Baker Lake, placing it in one of the more remote stretches of the Canadian subarctic. Its water surface covers 421 km², and including its islands the total area reaches 447 km². The Perry River drains the lake northward, eventually reaching the Queen Maud Gulf.

The lake's coordinates place it at approximately 66°40′N, 102°49′W, well above the treeline in open tundra terrain. The Perry River connection to the north provides a natural paddling corridor toward the Queen Maud Gulf, and the lake itself is large enough that wind and wave conditions can become significant factors for paddlers. Given the lake's size and its subarctic location, weather can change rapidly and cold water temperatures should be expected throughout the paddling season.

Nearby water bodies of interest to paddlers include the Perry River, which flows from the lake northward, as well as more distant features such as the Thelon River to the southeast. The surrounding tundra landscape and the lake's proximity to the Arctic Ocean suggest a paddling environment characterized by open, exposed conditions with minimal tree cover or wind shelter.

No specific access points, facilities, or amenities for paddlers are documented for MacAlpine Lake. Given its extreme remoteness — roughly 400 km from the nearest town of Baker Lake — any expedition to this lake would require thorough logistical planning, including fly-in access and full self-sufficiency. The area around the lake is known to support lake char (lake trout) and Arctic char in nearby waters, which is consistent with the cold, clear water typical of subarctic lakes in this region.