The collapse of Forts Henry and Donelson made Polk's position at Columbus untenable; the Confederates were forced to abandon The Gibraltar of the West. His line shattered, Johnston abandoned Bowling Green on February 11, 1862, retreating first to Nashville, then further south to join P. G. T. Beauregard and Braxton Bragg at Corinth, Mississippi. Cumberland Gap, the final piece of Johnston's line, finally fell to Union forces in June 1862.