Greece

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

History of Greece
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. (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 was a Greek trireme. (DW: Enlightenment)