Not a true 0 gauge railway, the Raylo set was closer to 00 in size, but deserves a mention here as the first railway set produced by Meccano Limited in 1915, five years before 0 gauge Hornby Trains were launched and twenty three years before the launch of Hornby Dublo.
The Raylo set was a game rather than a train set, and featured a clockwork 0-4-0 loco (without tender), and a set of rails, in a leather bound carton.