I have a collection of swim caps, as anyone who swims regularly, too many to wear, even pulled one on top of another. The crazy thing is I much prefer to wear no cap at all. In open water, caps need to be bright, even if they are really a lousy way of sticking out and being visible. Caps are good identifiers, though – if you know who is wearing which colour hat before going in, and you can identify people, when in the water there is little to identify people by, especially at a distance. They can be good identity markers too - clubs, people, places and memories are all bound up in this simple item of clothing.