Arcadia (planet)

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Arcadia was a Human colony world in the 26th century. It was a non-technological paradise and served as a living specimen for a centuries-long experiment. (NA: Deceit)

Diamonds could be found on Arcadia and were very valuable. (TW: Kiss Kiss, Bang Bang)

The Fall of Arcadia was an important event during the Last Great Time War, where the planet fell to the Dalek Empire. (DW: Doomsday)

It is unknown if the term "fell" means Arcadia came under the Daleks' control or if it was destroyed entirely. The various references to Arcadia may or may not refer to the same place.

Amy Pond and The Doctor visited Arcadia. (DW: Vincent and the Doctor)