Magnus Manske Day is January 25, which commemorates the day in 2002 when Wikipedia switched to the new PHP software. This is an important day to Wikipedia. Jimbo Wales has proclaimed:
I hereby decree, in my usual authoritarian and bossy manner, that today shall forever be known as Magnus Manske Day. Wikipedians of the distant future will marvel at the day when the new software era dawned upon us. Tonight at dinner, every Wikipedian should say a toast to Magnus and his many inventions.
... of Rail Travel[?], Keighley and Worth Valley Railway
National Museum of Photography, Film and Television, Bradford
Royal Armouries Museum[?], Leeds
West Yorkshire Folk ...