In Ireland and the United Kingdom, what Americans and Australians call "lap swimming" is called "lane swimming". While working on this note, we found a nice page on the loneswimmer.com website that explains the rules for lane swimming quite nicely; you can find it HERE. Note: In some UK pools, adjacent lanes circle-swim in opposite directions, clockwise/anti-clockwise/clockwise/etc., this avoids those painful finger-tip-taps that sometimes happen when the individual on the other side of the lane line is going in the opposite direction from you.