Stuttgart
From Tardis Wiki, the free Doctor Who reference
Stuttgart was a city in Europe. When the Eighth Doctor brought Mary Shelley to Vienna in 1873, she tried to guess where they were, and Stuttgart was one of the wrong guesses. (AUDIO: The Silver Turk)
In the 16th century, Frankfurt was considered a free Protestant city. (AUDIO: The Marian Conspiracy)
In 1930, the Eighth Doctor told Lord Tamworth that he was Dr Johann Schmidt of Stuttgart. (AUDIO: Storm Warning)