The foghorn at Sumburgh in the Shetland Islands of Scotland is powered by more than one 44hp Kelvin K-Series diesel engines, powering the Alley and MacLellan compressors which blow the horn itself.
"Just so's you know," writes JJ Jamieson, who posted this footage to YouTube, "the horn was originally much louder at the end, but YouTube's audio algorithm turned the volume down. I tried several versions but it wasn't having it."
