Star Trek Expanded Universe

Starbase Expanse 3 was a Federation deep space station on the edge of the Typhon Expanse.

The station, constructed by at least 27 different races and societies over the period of millenia, posed problems for Starfleet as many sections (approximately 87%, according to Antonio Fernandes) were shielded from external sensors and LCARS systems incompatible with existing computer systems; Starfleet was the latest occupant from at least 2368 until the entire crew disappeared without a trace in 2372.

The station had one section with bubble-like appendages all over; Benjamin Caldwell identified a language in this section as a form of Straulausian (with two vowel shifts). Another section was sleek and smooth, dark gray in color, with no apparent windows, hatches or doors. Station ops, and its lobby, were created by an ancient race related to the Beddinians. (Star Trek: The Cantabrian Expeditions: "Catalyst, Part One")

The USS Huntly accompanied Helena Bourget and her ship to Starbase Expanse 3 in 2368 to ensure she arrived in Federation space safe and sound. (Star Trek: The Cantabrian Expeditions: "Breaking Benjamin")