Castle

A castle was a fortified stronghold, usually used as a residence for royalty or nobility.

Warrior's Rest was a castle on Treva. 

Naghai Keep was a castle in Korto City on Bajor. 

Organia had a large ruined castle not far from the village where the Organian Council of Elders dwelled. 

In 2267, Korob and Sylvia created an illusory castle on Pyris VII. 

A castle on a planet in Sector Vega 6 was inhabited by. It was destroyed in 2264 by the USS Enterprise (NCC-1701) to prevent the starship from being dragged down to the planet by Chang's tractor beam. 

A planet in a medieval stage of development was ruled by Inquisitors who lived a castle. 

One President of the United Federation of Planets promised Vina (then a child) a castle of her own if she ever visited her homeworld. 

In 2266, Lewis Rosenhaus wondered if the Capellans used Capellan acid for sieges of the castle.