Baden Mainline
After the all-important north–south axis as well as links to the Lake Constance region had been established by the Baden Mainline, the remaining network expansion plans concentrated on opening up the area of Pforzheim with the Karlsruhe–Pforzheim–Mühlacker route (opened 1859–1863), linking up the Odenwald and Tauberfrankens with the Baden Odenwald Railway (Heidelberg–Mosbach–Würzburg, opened 1862–1866) and forging a direct link from Karlsruhe to Konstanz, without the diversion via Basle, in the shape of the Black Forest Railway (opened 1866–1873).