The Beta Cassius system was an inhabited system. Prior to 2364, a planet of this system, Haven, had by treaty become a protectorate of the United Federation of Planets. One of the passages into the system was by a stargate.

On stardate 41294, two ships visited the system: the USS Enterprise-D for shore leave, and a Tarellian starship attempting, successfully, to contact Wyatt Miller. (TNG: "Haven")