Weslemkoon Lake is located in the Township of Addington Highlands, Ontario, Canada, near Denbigh and about 110 km (68 mi) north of Belleville.

[1] The lake is characterized by a rocky shoreline, with numerous bays and coves that are home to bogs, and swampy areas.

Lake Weslemkoon is located within Algonquins of Ontario Settlement Area, which is unceded land.

[2] When heading north on the lake from the southern end, a viewer would notice a lighthouse that has stood since the 1920s and, up until the installation of a large orange flashing beacon placed on top of a 55-gallon drum and mounted to a rock, served to mark the narrow entrance into the main body of the lake.

Wildlife include: common loon, great blue heron, black bear, ruby throated hummingbird, pileated woodpecker, bald eagle, beaver, moose, great horned owl, lynx, and bobcat.