Lighthouse bagging

Some people like to "bag" Munros or Corbetts but a recent a Guardian article describes the somewhat different challenge of lighthouse bagging:

"You need a head for heights and sturdy sea legs to conquer these pinnacles of engineering achievement and testimony to our ceaseless struggles with the sea. The walkers who bag Scotland's 284 Munros have it easy compared with those who undertake the ultimate challenge: visiting all 209 working lighthouses that mark the most treacherous corners of Scotland's coast".

The term pharology is used for the study of signal lights and lighthouses, It comes from Pharos - the huge lighthouse of Alexandria that was built in the third century BC and was one of the tallest man-made structures on earth for centuries.