Circle swimming is the norm at most organized Masters workouts. Notice in the diagram that it is not a true circle, but you get the point. Outdoor pools are different than indoor pools, and old pools are different than new pools, but they tend to follow a basic design that serves their intended users: black lines on the bottom indicate the center of each lane, and black crosses mark each wall. Use these markings in the pool just as drivers use them on the road.

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