In 1861, the Louisville and Nashville Railroad, which I-65 largely parallels today, connected the mid-South to the Ohio River and the industrial centers of the North. During the war, it became a vital Union supply line that brought invaders into both Tennessee and Kentucky and a target for Confederates, who established Camp Trousdale at Portland, Tennessee, as a major induction and training center because of the railroad’s proximity. In February 1862, Union Gen. Don Carlos Buell took Bowling Green in southern Kentucky, then moved down the railroad and occupied Nashville, the Tennessee capitol. Retreating Confederates destroyed railroad bridges, trestles, and facilities, but by April trains again operated between Louisville and Nashville, supplying Union armies. In May, Confederate Gen. John Hunt Morgan invaded Kentucky and destroyed railroad cars at Cave City. In August, he raided Gallatin, Tennessee, and closed South Tunnel between Portland and Gallatin. Late in December, Morgan again destroyed railroad equipment and tracks in Kentucky. After the spring of 1863, the line experienced little disruption, and at many places Union soldiers manned small forts to protect the railroad.