Chalna was an inhabited planet. This was the homeworld for the Chalnoth, an anarchistic humanoid species.
While commanding the USS Stargazer in 2354, Captain Jean-Luc Picard visited Chalna. He recalled his visit there to Esoqq when they were imprisoned together twelve years later. (TNG: "Allegiance")
In 2371, the location of Chalna was labeled in the star chart Data and Picard were studying in stellar cartography aboard the USS Enterprise-D. (Star Trek Generations, okudagram)