Darthen

From Memory Alpha, the free Star Trek reference

Darthen was a coastal city on the planet Rekag-Seronia.

During the 2360s, Darthen had remained neutral throughout the war between the Seronians and the Rekags. The city had loyalists from both sides residing there, and as a compromise it was chosen by Ambassador Ves Alkar for the location of a peace conference between the two. (TNG: "Man of the People")