The game’s afoot as armchair detectives mark Sherlock Holmes Day

The Sherlock Holmes Society of London visited the Reichenbach Falls earlier this month (AP)

From 221B Baker Street in central London to a cliffside waterfall in the Swiss Alps, generations of armchair detectives are celebrating International Sherlock Holmes Day.

On Friday, fans will mark author Arthur Conan Doyle’s birthday in tribute to the author and his most famous character, whose adventures continue to shape popular culture around the world.