Den Optiska Telegrafen (The Optical Telegraph)

Grisslehamn was once an important communication hub in Sweden, sending information east as fast as possible. At first, this was done orally & with letters, then telegraphs and phones, however, there was 1 strange step in this evolution, the optical telegraph.

The system was invented in 1794 by Abraham Niclas Edelcrantz and used a binary number system that allowed it to send messages rapidly with the 10 shutters on its roof, which could be set in 1,024 different combinations. Each station was just within view of the next.

This 2015 structure is a replica of the original 1796 building.