It's easy to see the appeal of taking a cooling dip in the sea on a hot summer's day, but taking the plunge into an icy lake or chilly river when it's cold outside? For many people, the idea seems like madness. But for a growing group of brave souls, outdoor swimming in all weather has become a popular pastime.
Would you take the plunge? Click through this gallery to find out why wild swimming has suddenly become so popular.