Carnival Cruise Lines is the world's largest cruise carrier -- with 24 ships and approximately 4.5 million annual passengers as of 2014 -- but it isn't immune to the luggage limitations you'll run into using any major cruise line. Before leaving for your departure port, be sure to know what you can and can't bring on a Carnival cruise to avoid any unnecessary delays or inconveniences.

Suitcase Size

Be selective with how much you decide to pack in your suitcase. Carnival cruises can be as long as 23 days, but for all cruises, guests can have only two suitcases that weigh no more than 50 pounds each. But don't worry about running out of clothes -- all Carnival ships have onboard laundry facilities. Additionally, suitcases cannot be any taller than 16 inches or wider than 24 inches, though they can be as long as you want, according to Carnival's website.

No Weapons

Carnival ship security personnel may confiscate any items they feel are dangerous. This includes all firearms -- including replicas -- ammunition, Tasers, pepper spray or mace, martial arts paraphernalia and similar items. You can bring a knife on board as long as its blade is shorter than 4 inches. Don't bother bringing any fire-related items with you, either; Carnival prohibits candles, incense and lighter fluid. If you accidentally bring a prohibited item with you -- provided it isn't an immediate threat to passenger safety -- Carnival will usually hold it for you until you return to port. According to Carnival's website, security staff screen all bags for dangerous items.

Excursion Gear

If your cruise includes an excursion where you would need diving equipment like diving knives, you can leave these items with ship security and check them out when you need them. You'll have to rent canoes or small boats when you reach your destination ports, however, because Carnival forbids these items in passenger luggage. Boogie boards are allowed as long as they are shorter than 42 inches. In general, diving gear is prohibited for Carnival cruises. This includes dive tanks and spears. If you're planning on a beach celebration at your destination port, plan to purchase fireworks or coolers larger than 1 cubic foot when you arrive.

Food and Drink

Carnival cruises usually provide plenty of food and drinks for all passengers, but passengers with dietary restrictions or particular tastes should verify that what they want to bring on board is allowed. If you're at least 21, you can have one unopened bottle of wine or champagne in your carry-on -- but no beer or liquor. You can bring food onto Carnival cruises, but it must be unopened, prepackaged and ready to eat. Don't bring anything you whipped up at home -- Carnival completely prohibits these items to prevent contamination.