The gambling restrictions also vary between cruise lines. Carnival Cruise Line, Celebrity Cruises, Holland America, Norwegian, and Royal Caribbean require passengers to be 18 years of age or older. In order to get a basic grasp on the laws of international waters, start at the coastline. Extending 12 nautical miles from a country's coastline is what's known as 'territorial waters.' Success Universe's boat and other Hong Kong ships leave port late each evening, open their casinos once in international waters, and allow patrons to gamble through the night.

You may think anything goes in those lawless international waters, but truth is, the cruise lines maintain fairly strict policies governing the age at which you can drink booze, gamble and occupy a cabin alone. Typically, the combination key/ID/charge cards each passenger is issued clearly indicate if the holder is under age. The only hope of getting a drink on a cruise ship if you're an underage teen is getting some older sucker to buy it for you when no one's looking. If a cruise line wants to be hard nosed, they can eject transgressors from the ship at the next port of call -- at their own cost. Drinking laws may be much more lenient on shore, for instance in the Caribbean.

Of course it wasn't always this way. Just a decade ago rowdy high school groups were a common sight on big cruise ships, especially during the spring break months. Barely chaperoned mobs of young binge drinkers would practically take over a ship, hogging deck chairs, spilling out of cabins, passing out in hallways, puking on stairs and boldly staggering up to adults in bars asking for drinks (which, if they were cute enough, they usually got!).

Since those wild days, cruise lines have toughened up their policies quite a bit. Unsupervised teen groups are not permitted on board any more. Not to say you won't ever encounter obnoxious adolescents -- with more and more families cruising, there are a lot of teens sailing these days -- but mom and dad are on board to, hopefully, keep their offspring in line. Now, if you happen to be a civilized teen looking to cruise solo with a friend or two, you're basically out of luck.

Age Policies of the Major Lines

Carnival (www.carnival.com)

All passengers must be 21 years old to drink alcohol no matter where the ship is sailing. You must be 18 to gamble in the casino; if you're under age 21, there must be at least one person in the cabin over 25.

Celebrity Cruises (www.celebritycruises.com)

All passengers must be 21 years old to drink alcohol, with the exception of Europe, South America and Australia cruises if parents cruising with their children sign a waiver allowing their 18 to 20 year olds consume alcohol. Passengers must be 18 to gamble in the casino (and 21 on Alaska cruises). If you're under age 21, there must be at least one person in the cabin over 21, unless minor children are cruising with their parents or guardians and staying in an adjacent cabin.

Costa Cruises (www.costacruises.com)

All passengers must be 21 years old to drink alcohol and 18 to gamble in the casino. All passengers must be 21 years old, or have at least one person in the cabin over age 21. During certain times of the year, like Spring Break, passengers ages 21 to 24 must have one person at least 25 years old in the same cabin.

Crystal Cruises (www.crystalcruises.com)

All passengers must be 18 years old to drink beer and wine, and 21 to drink the hard stuff; however when the ship is docked or anchored in an American port, or within the 3-mile limit, the drinking age is 21 for all alcoholic beverages. To gamble in the casino, passengers must be 21 or older. Those 18 and younger must share a cabin with a parent or guardian 21 or older.

Disney Cruise Line (www.disneycruiseline.com)

All passengers must be 21 years old to drink alcohol and you must be at least 18 to occupy a cabin without an adult.

Holland America (www.hollandamerica.com)

All passengers must be 21 years old to drink alcohol no matter where the ship is sailing, 18 to gamble in the casino, and if you're under age 21, there must be at least one person in the cabin over 25.

Norwegian Cruise Line (www.ncl.com)

Passengers ages 18 to 20, with the written consent of their parents or guardian, can purchase beer or wine for themselves only when the ship is sailing in international waters (except in Alaska and Hawaii, where you must be 21 years of age to consume or purchase alcohol or any kind). To gamble in the casino, passengers must be 18.For cabins, at least one person must be 21 or older (unless cruising with parents in an adjoining cabin or if you can prove you're a married couple under age 21).

Princess Cruises (www.princesscruises.com)

All passengers must be 21 years old to drink alcohol or gamble in the casino; those 18 and under must share a cabin with someone 21 or older.

Regent Seven Seas (www.rssc.com)

Gambling Age On International Waters 2020

All passengers must be 21 years old to drink alcohol or gamble in the casino; and 18 is the age minimum to occupy a cabin.

Royal Caribbean (www.royalcaribbean.com)

All passengers must be 21 years old to drink alcohol, with the exception of Europe and South America cruises if parents cruising with their children sign a waiver allowing their 18 to 20 year olds consume alcohol. Passengers must be 18 to gamble in the casino (and 21 on Alaska cruises). If you're under age 21, there must be at least one person in the cabin over 21, unless minor children are cruising with their parents or guardians and staying in an adjacent cabin or if underage married couples can show proof of marriage certificate.

Silversea Cruises (www.silverseacruises.com)

All passengers must be 21 years old to drink alcohol on all cruises, and 18 to gamble in the casino or occupy a cabin alone.

Windstar Cruises (www.windstarcruises.com)

Gambling Age On International Waters Found

All passengers must be 21 years old to drink alcohol; 18 to gamble in the casino; and if you're under age 21, there must be at least one person in the cabin over 25.

Gambling Age On International Waters Today

As for cabin age minimums, many cruise lines make an exception for parents traveling with children and occupying two adjoining (or nearby) cabin -- even if it's not officially condoned, it's often overlooked.

Gambling Age On International Waters Act

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