Greece

Greece was a country in Southern Europe, on Earth. Alien frequently became involved throughout its history.

History
In ancient times, the Immortals were worshiped as gods by the Greeks. (PDA: Deadly Reunion)

The Doctor claimed to have met the legendary Greek hero Theseus. (DW: The Creature from the Pit, The Horns of Nimon)

Circa 1200 BC, the Greeks participated in the Trojan War. This was when the First incarnation of the Doctor met Katarina. (DW: The Myth Makers)

Greek civilization was influenced by the Dæmons and Scaroth. (DW: The Dæmons and City of Death)

The Greek philosopher Bigon was abducted by the Urbankans. (DW: Four to Doomsday)

The Doctor claimed to have met both Alexander the Great and Pyrrho. (DW: Robot, The Keys of Marinus)

One of the ships used by the Eternals in their contest for Enlightenment resembled a Greek trireme and was crewed by Greek sailors. (DW: Enlightenment)