The Chicken Rock Lighthouse is an active 19th century lighthouse, located on Chicken Rock an isolated island at the southern end of the Isle of Man. Completed in 1874, the 44-metre-high (144 ft) tower is constructed of tapered granite and was designed by David and Thomas Stevenson. The need for the light on Chicken Rock was identified as early as 1866, due to the problem of fog obscuring the two lights on the nearby Calf of Man, hindering safe passage through the North Channel between Scotland and Ireland.