Alien Worlds
Telos

Telos was originally an ice planet in which the Cryons could live. The Cryons were then driven underground by the high temperatures as the temperature on the surface rose. The Cybermen, driven from their worlds by the Alliance, conquered Telos and the Cryon cities.

The cities were used by the Cybermen as a cryogenic facility. When the second Doctor, along with a party of archaeologists, visited Telos they found an arid, mountainous planet. However, under the surface lay the Cyber tombs.

Television adventures on Telos:

The Tomb of the Cybermen
Attack of the Cybermen

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