Atlin Lake

Infobox lake
lake_name = Atlin Lake
image_lake = Tagish Lake.jpg
caption_lake = A portion of Atlin Lake (on the right half of the image) during the winter, as seen from space. The lake seen on the left half of the image is Tagish Lake
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location = northern British Columbia
coords = coord|59|30|N|133|45|W|region:CA-BC_type:waterbody|display=inline,title
type =
inflow =
outflow = Yukon River
catchment =
basin_countries = Canada
length =
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residence_time =
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cities = Atlin

Atlin Lake is a lake in northwestern British Columbia and is that province's largest natural lake. The northern tip of the lake is in the Yukon, as is Little Atlin Lake. However, most of the lake lies within the Stikine Region of British Columbia. Atlin Lake is considered the source of the Yukon River and flows into Tagish Lake.

The name comes from "Áa Tlein", the Tlingit word for "big body of water".

The community of Atlin, British Columbia is located on the eastern shore of the lake and the southern part of the lake is in the Atlin Provincial Park and Recreation Area.