Turnaround day is the day when one set of passengers departs the ship and another set embarks. That sounds simple, and cruise lines are experts at making it look easy from the passenger's point of view, but the reality is that turnaround day is a fast-paced race day for the crew.

The list of what must be handled in a short amount of time is mind-boggling. Besides managing passenger flow off and onto the ship, the ship's crew must restock food and beverages, refuel, offload garbage and waste, and sometimes orient new crew members. The Centers for Disease Control dictates many of the cleaning and maintenance processes that must take place on turnaround day, including emptying dispensers and sanitizing surfaces that might have been missed during standard cleaning during the cruise. And think about the laundry. Every single sheet, towel and duvet cover gets washed on turnaround day.

Then there is the luggage. An average of three pieces of luggage per stateroom must be sorted and unloaded at the pier before passengers begin walking off the ship. In conjunction with the luggage dispersal, the ship and its passengers, crew and the luggage must be cleared by customs and immigration officials. That includes paperwork, inspections and even drug-sniffing dogs at some ports. The reverse process of loading the luggage of new passengers begins just hours after the offload.

Staterooms must be cleaned and made ready for arriving cruisers. This is complicated by special requests, sail-away gifts that have been ordered and stocking staterooms with perks provided to rewards program members at various status levels.

Mandatory passenger safety drills required by SOLAS are one more thing the crew must squeeze into the busy day. Spa tours, drink package and excursion sales, prepping and serving multiple meals, and assisting a ship full of disoriented passengers are all turnaround day tasks that require an all-hands-on-deck attitude from the crew to make the day flow smoothly.