Troyius
Troyius was an inhabited planet, the outer of the two, the other being Elas, found within the Tellun system in the Alpha Quadrant. This was the homeworld of the Troyians, a spacefaring humanoid species. 

In the mid-23rd century, this planet's system was located in a border area near the Federation-Klingon border.

In 2256, this planet was mentioned with the star system's name on the star chart "Alpha/Beta Quadrant Overview" in the ready room aboard the . ()

In 2257, during the first , this planet's system was occupied by the Klingons. ()

In 2258, the planet's location was labeled on a star chart seen on the main viewscreen of the . ()

In 2259, the location of this planet was labeled on a stellar cartography chart that was seen on the 's ready room viewscreen. This planet's symbol had a blue color, indicating that it was affiliated with the . () 

The planet had rich deposits of dilithium ("radan" in the Troyian language). In 2268, both planets possessed the capability of mutual destruction. The wedding of the Dohlman of Elas, Elaan, to the ruler of Troyius preserved the peace. ()

In 2399, this planet was mentioned with the star system's name on a Federation star chart that was in Fleet Admiral Kirsten Clancy's office at Starfleet Headquarters. The system was in or near Federation space. ()

Appendices

Background information 
According to Star Trek: Star Charts ("United Federation of Planets I"), in 2378, Troyius was a Federation member.

Apocrypha 
According to FASA's The Federation sourcebook, Troyius is the fifth planet in the Tellun system.

The Star Trek: The Original Series - Core Game Book says it's the fourth planet in the system.

External links 
 
 

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