Siegstrecke
The construction of the Sieg Railway from Deutz to Giessen (which started in 1859) enabled Nassau to negotiate with Prussia over the continuation of the line, since the planned Sieg line passed through the Dillenburg district, which was part of Nassau. Finally in 1860 an agreement between both states was concluded, which allowed Prussia to build the Sieg line. In return Prussia agreed to build the Pfaffendorf Bridge, which connected the line near Niederlahnstein with the West Rhine Railway ("Linke Rheinstrecke") in Koblenz finished the year before. The bridge was inaugurated on 3 June 1864. A continuation of the East Rhine line through Prussia was not possible for the time being, because the concession that the Rhenish Railway had received for the West Rhine line had specified that no concession would be given for a railway on the right bank of the Rhine before 1876.