There are at least two rival "World Championship" tournaments, one based in the UK and one in Germany.
The German one, centred on districts in the Ruhr valley, has been running annually since 1984. Some 200 competitors have taken part over that period. The venue varies, as it is customary for the winner of each event to host the next year's in their home town, and players come from all over the country. When I attended the one held in Ratingen in 2011 there was an entry list of forty-eight. (My excuse for coming 46th is that the group was then still using the 1978 Ravensburger board, to which I am no longer accustomed.) The whole event was a wonderful social occasion, the play sessions being interspersed with entertainments including talks, songs and general merry-making. A prominent young member of the play group is the multi-talented musician Tobias Krüger, who performs under the name MrTobiTill, and some of whose videos can be seen on YouTube - see, for example, "Beatsteaks".

Mind Sports Olympiad since 1997

The UK tournament is held annually as part of the Mind Sports Olympiad, initiated in 1997. There was a tournament in its first year, followed by a gap of nine years. I believe one was held in 2023 but was unable to get to it and am still awaiting the results. In 2024, however, the 50th anniversary of its first ever publication, I was able to get there for another tournament of 16 players and was pleased to meet old friends who had been taking part on and off since 1997, notably Steve Wright, Ken Wilshire, and the indefatigable Dario De Toffoli. AS this was only a few days ago as I write I can't update the list of winners below:

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