Saltok

The Saltok system was a star system proximate to both the United Federation of Planets and the Cardassian Union. As of the mid-24th century, the system was uninhabited. In 2355, Starfleet Intelligence agents aboard the civilian freighter Ulrika's Hope detected Cardassian ship activity in orbit of the Class-D moon of Saltok V. It was suspected that the Cardassians had constructed a monitoring station on that moon. (SCE eBook: Home Fires)

By 2370, a Federation colony had been established on Saltok IV, and when the Demilitarized Zone was established that year, the Saltok system was placed within it. (DS9 episode: The Maquis, Part I)