Derna

From Memory Alpha, the free Star Trek reference.

Derna is the small and uninhabited fourth moon of the planet Bajor.

In early 2375, Senator Cretak of the Romulan Star Empire asked Colonel Kira Nerys if her people could place a field hospital on the moon as large numbers of Romulans were dying on the long trip back to Romulus. The Bajoran Provisional Government quickly accepted this request from their allies and the hospital was constructed.

However, when a Starfleet transport carrying mainly injured Vulcans was denied access to the hospital, evidence emerged that the Romulans had begun arming the facility with plasma torpedoes. The Bajoran government objected to this action and demanded that the Romulans remove the weapons. The Romulans refused, forcing the two allies into a stand-off.

Colonel Kira took a small fleet of Bajoran impulse ships to prevent an approaching group of fifteen warbirds from reaching the moon. The ships, clearly no match even for a single warbird, held their ground until Starfleet Admiral William Ross told Cretak that if she did not remove the weapons, he would. (DS9: "Image in the Sand", "Shadows and Symbols")

Under the Starfleet threat the Romulans removed the weapons from the hospital, however, there is no reference made to the hospital itself. Most likely the facility remained, however unarmed, for the use of the Romulan wounded.

Bajor system
Bajoran sun
Bajor • Bajor VII • Bajor VIII
Jeraddo • Derna • Denorios belt • Bajoran wormhole