Fern Lake
Fern Lake Show map of Colorado Fern Lake Show map of the United States
Location	Rocky Mountain National Park, Larimer County, Colorado, US
Coordinates	40°20′12″N 105°40′35″W / 40.33667°N 105.67639°W / 40.33667; -105.67639
Primary outflows	Big Thompson River
Basin countries	United States

Fern Lake is an alpine lake in Larimer County, Colorado, United States. It is a major source for the Big Thompson River.

• U.S. Geological Survey Geographic Names Information System: Fern Lake