So, earlier this week BBC reporter Giles Dilnot asked people if they thought UKIP leader Nigel Farage had what it takes to be prime minister.
Which upset whoever was running the Twitter account for UKIP South Thanet, the constituency where Farage is hoping to become a MP in next year's general election.
Which was seriously awkward.
Because...
That's Westminster Cathedral, guys, not a mosque.
Anyway, whoever was running the UKIP account was quick to say sorry for their mistake.
And Dilnot accepted their apology.
BUT... Twitter doesn't like missing out on a golden opportunity for LOLs and the following day the #ThingsThatAreNotMosques hashtag took off.
Guardian blogger Alex Andreou led the way on Wednesday night.
And when he was done, the rest of Twitter took over.