Australia

Australia is both a continent and a nation located on Earth.

History
Circa 40,000 BC, five Euterpians stranded on Earth visited Australia and taught the Aborigines to sing. (MA: Invasion of the Cat-People)

Circa 35,500 BC, Australia was the site of Monarch's first visit to Earth. He abducted several Aborigines, including their leader Kurkutji, and gave them android bodies. He promised Kurkutji rulership of his people when Monarch made his final visit to conquer the planet. (DW: Four to Doomsday)

In 1863, the Doctor dropped off Charlie Fisher in Australia to give him a new life. (TVC: Backtime)

In the 1920s, the Doctor met Australian opera singer Dame Nellie Melba and learned her party trick of shattering glass with a high-pitched note. (DW: The Power of Kroll)

In 1932, the Doctor met Australian cricket champion Donald Bradman and took five wickets for New South Wales. (DW: Four to Doomsday)

In the 1970s, the Doctor, in an attempt to escape his exile, got his TARDIS to materialise in the Australian desert, where, with the aid of Murray Stevens and some Aborigines, he defeated Rudolph Steiner's plans. (TVC: Gemini Plan)

In 2017, the Doctor and his companions Jamie McCrimmon and Victoria Waterfield arrived on an Australian beach, where they soon became embroiled in the machinations of Ramon Salamander. (DW: The Enemy of the World)

In 200,100, Australia and its neighbors collectively formed Australasia. This area was depopulated by the Daleks when they attacked Earth. Whether the Bad Wolf entity restored the population of Australasia and the rest of Earth to life, as it did to Jack Harkness, is not currently known. (DW: The Parting of the Ways)

Other facts
One of the Doctor's later companions, Tegan Jovanka, was a native of Australia, having grown up on her father's farm near Brisbane. Her Aunt Vanessa was also from Australia. (DW: Logopolis)

The Doctor bought a beach-house in Sydney while his house in Kent was being painted. (NA: Sleepy)

Cities

 * Brisbane
 * Melbourne