page_title: Prussian semaphore system
section_title: Route
hierarchical_section_title: Prussian semaphore system / Construction and function / Route
caption_attribution_description: Verlauf des Preußischen optischen Telegrafs um 1835
context_page_description: The Prussian Semaphore System was a telegraphic communications system used between Berlin and the Rhine Province from 1832 to 1849. It could transmit administrative and military messages by optical signal over a distance of nearly 550 kilometres. The telegraph line comprised 62 stations each furnished with a signal mast with six cable-operated arms. The stations were equipped with telescopes that operators used to copy coded messages and forward them to the next station. Three dispatch departments located in Berlin, Cologne and Koblenz handled the coding and decoding of official telegrams. Although electric telegraphy made the system obsolete for military use, simplified semaphores were still used for railway signals.
context_section_description: The line began with Station #1 at the old Berlin Observatory in Dorotheenstrasse.  The construction of the first section – with fourteen stations – was completed by November 1832.  The route ran via the Telegraphenberg #4 in Potsdam across Brandenburg an der Havel to Magdeburg.
  The locations of the stations were chosen by O'Etzel himself.  In choosing, he took into consideration of existing structures - for example the village church in Dahlem.  He also had his team construct towers on existing tall buildings.
  In many places along the route, trees had to be felled or have their tops cut off in order to maintain the sight lines between stations.  French telegraph operators had already recognized that signals were hard to recognize if they came from stations placed before certain backgrounds, while signals from stations against an open sky were much easier to recognize.  For this reason, the Prussian stations were built on higher ground where necessary.  Later, such places were often designated as "Telegrafenberg" as with Glidow (station #5) or station #13 southeast of Biederitz.  Because the receipt and distribution of messages was intended only for dispatch stations at the beginning and end of the line, no great value was placed on connecting smaller localities and cities.  Frequently, stations were placed away from settled areas.  The last station of the first section was constructed on the tower of the Johannis-Kirche in Magdeburg.
  To hasten construction of the second and longer section between Magdeburg and Koblenz, the finance minister as well as the interior minister ordered all their subordinates to offer their total cooperation to the construction leadership.  This was done to avoid time-consuming territorial conflicts between local authorities.  If an agreement over the acquisition of a piece of land for the construction of a new station was not possible, expropriation of private lands could be undertaken in the worst case.  The line ran north of Egeln (Schloss Ampfurth), through Halberstadt, Goslar, Höxter to station #31 near Entrup where it turned in a southwesterly direction just before reaching Paderborn after crossing the Weser Uplands. Subsequently, it ran along the southern side of a line connecting Salzkotten, Erwitte, Soest, Werl, Iserlohn, Hagen, Schwelm and Lennep it made its way finally to Cologne via the stations Schlebusch (station #49), and Flittard (#50).  From there he route ran parallel to the east bank of the Rhine via Spich to Ehrenbreitstein.  The final station (#60) was built into the Ehrenbreitstein Fortress.  After the completion of construction and the start of operations of the whole system in 1833, it quickly became clear that the Rhine ferry crossing to Koblenz presented a major hold up in telegraphic traffic.  This could only be solved by expanding the line with an end station in Koblenz.  In the same year, station #61 was put into service in the Electoral Palace in Koblenz, which was then used as a barracks.  The palace also served as the administrative offices for the western section of the route.
  The route traveled over Hanoverian domain at stations #22 and #23 in Schladen and Liebenburg.  Likewise, stations #23 through #28 lay in the domain of the Duchy of Brunswick.  Negotiations with both governments for the acquisition of land and the construction of stations quickly met with success. Additionally, two stations were economized within the Brunswick domain by increasing the distance between stations #23, 24, and 25. After a year of service, it became clear that the wide interval between these stations led to frequent interruptions in visual contact during drizzly and grey weather.  In 1842 this problem was solved with the construction of station #24a near Mechtshausen. The entire route now comprised 62 stations.  They were on average 11 kilometres (6.8 mi) apart with the longest distance separating stations at 15 kilometres (9.3 mi)  and the shortest at 7.5 kilometres (4.7 mi).
  There were only two dispatch stations, one at each end of the line.  Koblenz was the seat of the Oberpr
caption: full route of the telegraph line across Germany
exif: {}