The New Colonies were United Federation of Planets colonies established in the Triangle, following the events that had led to the Khitomer Accords in 2293. (Star Trek: Accord, Star Trek: Avenger: "Belonging", "To Everything There is a Season") They were located in the direction of Cardassian space relative to the center of the Federation. (Star Trek: Avenger: "And the Stars Look Very Different Today")
One of the first three colonies, named Therlin, was established by Andorians. (Star Trek: Accord: "Last Chance")
Merdeka was a colony, later a Federation protectorate, established in the New Colonies territories in the 24th century. (Star Trek: Shadowstar Station)