Forest Lake is a city in Washington County, Minnesota, United States. The population was 18,375 at the 2010 census. It is located on the north shore of Forest Lake, one of the largest lakes in the Twin Cities metropolitan area. The city is located 20 miles north of the Twin Cities of Minneapolis and St. Paul. It is one of the fastest-growing cities in Minnesota. The city is home to a variety of businesses, including a large industrial park, and is a popular destination for outdoor recreation.