Generally, you do not need to bring your own beach towel on a cruise, as almost all major cruise lines (including Royal Caribbean, Carnival, Norwegian, and Disney) provide complimentary pool and beach towels for their guests. On the ship, these towels are usually available at large bins near the main pool decks or are placed in your stateroom upon arrival. When you go ashore at a port of call or a private island, you are permitted—and encouraged—to take these ship-provided towels with you for your shore excursions. However, there is a very important rule to remember: most cruise lines operate a towel tracking system. You are often required to scan your Key to the World card or SeaPass when checking out a towel, and if you fail to return it by the end of the cruise, you will be charged a "replacement fee" that can range from $20 to $30 per towel. While ship towels are functional and absorbent, some travelers still prefer to bring their own thin, quick-dry microfiber towel to save space in their shore bag, or because they want a unique design that is easily identifiable among the hundreds of identical blue or striped ship towels on a crowded beach. If you are trying to travel light, you can safely leave the bulky beach towels at home.