The Hanolan colony was the destination for USS Rio Grande, which transported a number of non-Starfleet evacuees from DS9, during the Circle's coup d'etat of Bajor, and subsequent siege on the station, in 2370. Nog was among the group traveling to the colony. (DS9: "The Siege")
This colony was only mentioned in dialogue.
According to Star Trek: Star Charts (p. 47, "United Federation of Planets I", "United Federation of Planets II") and Stellar Cartography: The Starfleet Reference Library ("Federation Historical Highlights, 2161-2385"), there was a star system named Hanolan, which might possibly be the location of this colony, in the Alpha Quadrant. The system's primary was a K-class star. In the late 24th century, this was a Federation system.