This conical beacon is assembled around a central pole. It is also called a “pole bonfire”, and this term expresses the original, Iron Age use of this type of beacon: it was easy and quick to set alight when a warning signal was needed. There were many of these kinds of simple beacons in the archipelago. This beacon was based on a 6.5- foot-tall (2-metre) unpainted coneshaped beacon that had been used since 1856 on Skräckskär, on the route between Lohm and Sottunga. A tall unpainted pole beacon 16.5 feet high (approximately 5 metres) has stood on Riddarklubb, a barren island north of Jurmo, since 1856. A similar pole beacon was built on Saarenpää in 1859 and stood 18.5 feet (5.5 metres) tall.