The Oeynhausen telegraph station is station no. 32 along the Berlin – Coblenz optical telegraph line that connected Berlin with the Prussian Rhein regions for communication purposes between 1833 and 1849. 
The telegraph line with a length of around 600 km led from Berlin via Magdeburg past Braunschweig to Höxter, Paderborn, Rüthen, Iserlohn, Cologne and from there via Siegburg to Coblenz.
Existing high buildings such as castle towers and churches were used in addition to the newly constructed station houses.

A characteristic feature of a telegraph station was a high mast with three twin arms that could be recognised from afar. 4,096 characters could be displayed in purely arithmetical terms with aid of these so-called indicators. Numbers, letters, syllables, words and complete sentences were communicated such as "why isn't the line working" or "nothing new!"

With "excellent" air, 1.5 to 2 characters per minute were communicated to the next station situated between 7.5 and 15 km away and usually perched on a hill; operation however had to be interrupted in fog or rain. A dispatch of 30 words reached Coblenz from Berlin in 1.5 hours. This was a master performance in terms of communication if it is considered how long a messenger on horseback needed for this distance. 

Operation of optical telegraphy was terminated after just 16 years because electromagnetic telegraphy had been invented. The telegraph houses were either sold or torn down.  

Station No. 32 Oeynhausen was sold in 1850 at the Nieheim town hall for demolition purposes. In 1978, members of the Oeynhausen homeland association excavated and laid bare the foundation walls of the station. Reconstruction of the station was then commenced with financial support from the Westphalian Department for the Preservation of Historical Monuments in Münster – this was completed in 1984.

The now rebuilt “Telegraphen-Etablissement” Nr. 32 shows the room of the Prussian telegraphers incl. indicator device and historical uniforms, reconstructed in cooperation with LWL-Preußenmuseum Minden. 
In the lower tower room an exhibition on optical telegraphy and the history of Prussia in Westphalia is located (currently in revision)

(1) Klara Heinemann / (2) Klara Heinemann