what is "cottingley fairies"?
The Cottingley Fairies appear in a series of five photographs
Cottingley Fairies
The Cottingley Fairies appear in a series of five photographs 
there are fairies at the bottom of my garden UNANSWERABLE
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Cottingley Fairies [SEP] Introduction
The Cottingley Fairies appear in a series of five photographs taken by Elsie Wright (1901–1988) and Frances Griffiths (1907–1986), two young cousins who lived in Cottingley, near Bradford in England. In 1917, when the first two photographs were taken, Elsie was 16 years old and Frances was 9. The pictures came to the attention of writer Sir Arthur Conan Doyle, who used them to illustrate an article on fairies he had been commissioned to write for the Christmas 1920 edition of "The Strand Magazine". Doyle, as a spiritualist, was enthusiastic about the photographs, and interpreted them as clear and visible evidence of psychic phenomena.