New New York
New New York was one of the main cities of New Earth and a recreation of New York on old Earth. It had a Duke, a police force (New New York Police Department), New New York Hospital is run by the Sisters of Plenitude, not physically in the city, and a population of at least 10 million. The Doctor jokingly referred it should be called New New New New New New New New New New New New New New New New York, pointing out that it was the 15th York to be constructed. (DW: New Earth)
History
It was founded as a city state after Earth was destroyed by Sol expanding, so most of the Human population moved there. The Doctor visited in 5,000,000,023 and stopped a sinister plot set up by the Sisters of Plentitude. (DW: New Earth)
However, life became harsh for the population, which mood-sellers selling mood drugs setting up shops in the Undercity - the dark slums, far below the upper levels of the city. in the year 5,000,000,029, a new drug, called "Bliss", was created, and the Upper City became addicted to it, a virus evolved in the chemical which killed everything in seven minutes flat. To protect the rest of the population, the lower city and the Motorway were sealed off and New Earth went under a automatic quarantine lasting fore one hundred years. The virus sealed off from both the Under city and the M87 Galaxy, it had nothing to feed on, so it starved to death, until it became extinct.
Eventually, 24 years later in the year 5,000,000,053, the Doctor visited the city again, first visiting Pharmacytown where some Pharmacists were selling mood patches, and managed to save the people on the motorway by unsealing the exits and opening the roof section, allowing those trapped to escape and recolonise the city. (DW: Gridlock)