Chaladra was a city on the planet Romulus.
History and specifics
In the year 2376, the scientist T'sart was killing any dissident members of his race in this settlement. He later encountered Ambassador Spock during the assignment and claimed that he had done the killings in order to get the Vulcan's attention so that he could ask for defection to the United Federation of Planets. (TNG - Maximum Warp novel: Dead Zone)