In 1979 and 1980, the section between Tsukaguchi and Takarazuka was double-tracked in sequence, and in 1981 the section between Amagasaki and Takarazuka was completely electrified.
1979～1980年にかけて塚口～宝塚間が順次複線化され、翌1981年に尼崎～宝塚間の電化が完了。