Pools

All but the smallest ships have at least one pool, some of them elaborate affairs with water slides or retractable roofs; hot tubs and whirlpools are quite common.

Pools may be filled with fresh or salt water; some ships have one of each. While in port or during rough weather, the pools are usually emptied or covered with canvas. Many are too narrow or too short to allow swimmers more than a few strokes in any direction; none have diving boards, and not all are heated. Often there are no lifeguards. Wading pools are sometimes provided for small children.