Since this proposal lacked political support, the plans came to nothing and meanwhile the Herbertingen–Isny railway was opened through the Württemberg Allgäu in various stages until 1880.

The second proposal resulted in negotiations between the two countries, although this was initially unsuccessful because Bavaria insisted on responsibility for the management of the entire line to Lindau.

The military was involved in the implementation: the tracks in the Württemberg area were commissioned for the Royal Württemberg State Railways (Königlich Württembergischen Staats-Eisenbahnen) by members of the Berlin railway regiment; its exercises sometimes involved participation in civil construction projects.

[4][5] The railway line connecting the two endpoints of Leutkirch im Allgäu and Memmingen are not direct, but instead have two long curves.

This curve came about due to the interest of the Earl of Waldburg-Zeil in having a rail link to Unterzeil, which lies below Zeil Castle.

At Tannheim the track takes another sharp turn to the east and crosses the Iller on a large viaduct; at this point the border runs along the river.