The fictional detective created by Sir Arthur Conan Doyle is Sherlock Holmes. Holmes, introduced in the 1887 novel "A Study in Scarlet," is renowned for his keen powers of observation and logical reasoning. He resides at 221B Baker Street in London, where he often solves complex cases with his trusty companion, Dr. John Watson. Holmes's character has become an icon of detective fiction, inspiring countless adaptations in literature, film, and television. His methods and the famous catchphrase, "Elementary, my dear Watson," have left a lasting legacy in the genre, influencing many other fictional detectives.