Vienna

Vienna was a city in Austria.

The river Danube flowed through the city. (AUDIO: A Requiem for the Doctor)

Around 2010s, it consisted of districts, one of which was called Floridsdorf. (AUDIO: The Sontaran Project)

Visits by the Doctor
The Fifth Doctor, River Song and Brooke visited Vienna in the 18th century investigating an alien trace. They arrived around the time Wolfgang Amadeus Mozart finished his Requiem in D minor. Together they prevented multiple fatalities at the premiere performance of the Requieum caused by Aqua Galatia. (AUDIO: A Requiem for the Doctor)

Vienna was particularly favoured by the Eighth Doctor. He left Samson and Gemma Griffin in Vienna while answering a distress signal from his future self. (AUDIO: Mary's Story) Later, he took Mary Shelley there on her very first journey in the TARDIS, attempting to reunite with Samson and Gemma. However, he got the date wrong and landed in 1873 instead of 1816. On this trip, he and Shelley battled Cybermen. (AUDIO: The Silver Turk) On another occasion, he battled a Bacchanite in Vienna and in the process inspired Johann Wolfgang von Goethe to write Faust. (PROSE: The Sorrows of Vienna)

After World War II, Vienna was administered by the Allied Control Console. The city was divided into four zones patrolled by the United Kingdom, France, the United States of America and Soviet Union.

In 1948, the Sixth Doctor, Constance Clarke and Flip Jackson visited Vienna. (AUDIO: Quicksilver)

The Fifth Doctor and Peri Brown also visited Vienna in 2100, if only long enough to deposit the Time Lord Techu there. (PROSE: Leap Second)

The Tenth Doctor once visited Vienna. He went to the Vienna State Opera to see Puccini's grand opera Turandot. The alien Anton Mordillo was the star of the opera. (COMIC: The Great Mordillo)

Other visitors
Sherlock Holmes and John Watson went on holiday to Vienna on the Orient Express. (PROSE: All-Consuming Fire) Indeed, Vienna was highly significant to Europe's railway network, being a stop on the Transcontinental Express as well. On 3 September 1939, Romana II rode the Calais-Vienna leg of that journey. (AUDIO: A Blind Eye)

Honoré Lechasseur and Emily Blandish once travelled back in time to Vienna to ensure that Adolf Hitler was admitted into the Vienna Academy of Fine Arts. (PROSE: The Sideways Door)

Commander Merx, a Sontaran, was shortly held in Vienna before being transferred to England to be used in the cloning experiments of Professor John Torrance. (AUDIO: The Sontaran Project)

Known residents
Wolfgang Amadeus Mozart was known to have lived in Vienna for a time, and indeed his DNA was once recovered from a harpsichord there and used to clone him. (AUDIO: My Own Private Wolfgang) He lived there in the 18th century with his wife Constanze who loved him very much. Mozart died because he was poisoned by Aqua Galatia. (AUDIO: A Requiem for the Doctor)

Toby the Sapient Pig was grown in a bell jar in Vienna. (AUDIO: Year of the Pig)

Hitler was educated in Vienna. (PROSE: The Sideways Door)

Johannes Rausch earned a degree in metallurgy at the University of Vienna. (AUDIO: Unregenerate!)

Around 2010s, the headquarters of the Auctioneers was in Floridsdorf district of Vienna. The Overseer operated from there. The office was closed after Christine Colley was captured by UNIT. (AUDIO: The Sontaran Project)

Hilberta's Hostel operated in Vienna in the 27th century. (PROSE: The Brakespeare Voyage)

Other references
The clone of Bertie Potts, who introduced himself as the British consul in Ur, claimed that he was hoping for a posting in Vienna. (AUDIO: The Boundless Sea)