Affectionately known as "Butterfly Town, USA," Pacific Grove (population 16,850) is located on the tip of the Monterey Peninsula. Founded as a religious retreat in 1875, Pacific Grove has developed into a beautiful small town, characterized by adorable Victorians and tree-lined streets. In the months between October and March, P.G., as it's known among locals, is host to thousands of Monarch butterflies, which mysteriously migrate from Canada and Alaska each year.