The passenger makeup varies, depending on the time of year and where the ship is based. During the Caribbean season (late fall through early spring), Independence of the Seas' American passengers are in the majority, with a strong showing of travelers from the U.K., Mexico and Spain, in particular. During its summer sojourn in Southampton, when it offers cruises to both the Baltic and the Med, as well as short-break cruises, Brits make up the vast majority of passengers. 

During vacation periods, kids make up more than one-third of the passengers, and a significant number are teens. During periods other than school holiday breaks, the ship feels less like an all-family resort destination, though the ship's Adventure Ocean program operates year-round. 

The ship makes an effort to accommodate travelers with special needs. There are wheelchair-accessible cabins with roll-in showers, transfer lifts in one pool and one whirlpool, and lowered tables in the casino. A room is equipped with an Infrared Assistive Learning System, and the ship's daily newsletter is available, upon request, in braille. 

Although the ambience onboard is conducive for a variety of passenger types, this is a tough ship for solo travelers. So many passengers travel in groups of family members or friends that all but the most gregarious may find it hard to connect with fellow singles, though there are occasional meetups for solo travelers. One suggestion: Consider signing up for Cruise Critic's Meet & Mingle gathering.

On an eight-night cruise, there are two formal nights, though formal on Indy is better defined as "smart casual" -- very few people dress up in tuxedo or full ballgown/cocktail dress attire. Most men wear a jacket and shirt and women will opt for a nice dress. The other nights are resort casual (tropical sundresses and pants outfits for women, khakis and shirts for men).

During the day, dress is casual (shorts, T-shirts, flip-flops).

Royal Caribbean passengers are charged $14.50 per person, per day ($17.50 for suite guests). Gratuities can be prepaid or will be added on a daily basis to passengers' SeaPass accounts during the cruise. Passengers can modify or remove gratuities by visiting the guest services desk while onboard. An 18 percent gratuity is automatically added to bar tabs and spa treatments. The currency used onboard is U.S. dollars.

Note: Australians and New Zealanders do not have the stateroom service charge added to their account; fares automatically include this gratuity as long as the cruise was booked in AU or NZ dollars.