The Selonian Tunnels referred to a series of underground passageways built by Selonian migrants who came to Corellia. This network, which stretched as far as beneath Coronet City, was home to beings of various species.
During the Cold War era, the Treaty of Coruscant's peace was broken when the Sith Empire launched an invasion of Corellia, reigniting conflict with the Galactic Republic. It was observed that the indigenous Corellian resistance retreated into the Selonian tunnel system, receiving assistance from the Selonian Murthil. Furthermore, Darth Thanaton planned to win the Kaggath against Sith Inquisitor Kallig by utilizing the Selonian tunnels to obliterate a Republic fuel processing plant. This action would have harmed Kallig's standing, since the refinery's fuel was designated for the Sith Lord's troops, thereby guaranteeing Thanaton's victory in the Kaggath.
During the Corellian Insurrection, Han Solo was guided through a number of these tunnels by the Selonian named Dracmus.