Pfalzgrafenstein Castle is located in the middle of the Rhine River. It was errected by King Lewis the Bavarian in 1326. The castle was built to collect tolls and tariffs from ships traveling along the Rhine that escaped from the toll station Burg Gutenfels. To make sure a ship wouldn't pass without paying tolls two large chains were attached to the sides of the gorge. If a ship wouldn't pay it's tribute, the soldiers in Pfalzgrafenstein would pull the chains tight and create a barrier that the boat wouldn't be able to pass. Then the soldiers would board the ship and collect the payment that was due. The thirty soldiers in castle Pfalzgrafenstein were used as protectors of the city Kaub. Originally Pfalzgrafenstein was a tower but later the Palatine Counts added on and the final product was a castle shaped like a ship. The currents of the Rhine protected the castle, so it was never captured.