Prussian semaphore telegraph between Berlin and the Rhineland
A cabinet order of 21 July 1832 determines the construction of a semaphore line from Berlin via Cologne to Coblenz
This was required to enable a rapid communication link between the Prussian heartlands and the Prussian Rhine regions. The semaphore line had a length of around 600 km and consisted of 62 stations spaced at intervals of 7 to 14 km. Information was transmitted using a signal system. A telegram required around 30 hours from Paris to Berlin.