Station Salem-One

From Memory Alpha, the free Star Trek reference

Station Salem-One was a station of unknown affiliation and location.

Captain Jean-Luc Picard once compared Station Salem-One to Pearl Harbor and noted that it was remembered as "the stage for a bloody preamble to war." (TNG: "The Enemy")

It is entirely possible that Station Salem-One was in fact, the heart of the Earth-Romulan War or at least one of the major battles that are part of that conflict. It may have also been the site where the conflict between the Federation and Klingons was ignited in the early 23rd century.