A marathon swim is a long-distance swimming event that typically covers a distance of 10 kilometers (6.2 miles) or more. These swims can take place in various bodies of water, including oceans, lakes, and rivers. Marathon swims are often organized as races, but they can also be undertaken as personal challenges or part of open water swimming events. Participants in marathon swims must be physically fit and trained for endurance swimming. They often face challenges such as changing water temperatures, currents, and waves. Safety measures, including support boats and lifeguards, are usually in place to ensure the well-being of swimmers during these demanding events.