Starbase 19 was a Federation Starfleet starbase first designated in the early 23rd century.

The USS Enterprise was en route to Starbase 19 in 2267, when they diverted to respond to a distress call from planet Donico II. (TOS - Constellations short story: "See No Evil")

Starbase 19 was one of two Starfleet facilities closest to the last reported position of the USS Sphinx, although there were no records of the ship docking there. (TOS - Section 31 novel: Cloak)

By 2270, Starfleet's Bureau of Unexplored Territory maintained on office on the starbase. In 2270, the Bureaus' head, Admiral Hiram Kawakami, contacted Captain James T. Kirk aboard the Enterprise and told him about the time-delayed message that the starbase recieved from Black Box Nebula Station One. (TOS novel: Corona)

In 2280, Starbase 19 was the closest Federation presence to Belle Terre at the time it was initially settled in the late 23rd century, being roughly ten weeks away at warp four-point-five. (TOS - New Earth novel: Wagon Train to the Stars)

In 2285, the Enterprise stopped at the station to pick up Ambassador Robert Fox, and replacement crew members. The Orion agent, Enigma infiltrated the Enterprise at the station. (TOS comic: "Who Is... Enigma?")

In 2372, Starbase 19 was the site of a security summit called by Admiral Jeremiah Hayes. (TNG - Slings and Arrows eBook: The Insolence of Office)

In 2375, Starbase 19 was the assembly point for the Twelfth Fleet in preparation for an offensive to retake Betazed from the Dominion. However, Dominion forces struck first, destroying the starbase and thirty-six starships. (TNG novel: The Battle of Betazed)

References to Starbase 19 being a significant distance from the heart of the Federation in the New Earth series, and being in close proximity to Betazed in The Battle of Betazed, suggests the designation may have been reassigned to a new facility at some time between the two stories.

Federation starbases
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