It was just over a year ago that Royal Caribbean launched Harmony of the Seas from the port of Southampton after being constructed by 2,500 workers for just under $1 billion. If that sound like a lot, it’s really not. The U.S. Navy’s new aircraft carrier will dominate the seas at a price tag of $13 billion. That one ship is part of a plan to build a 308 ship fleet will cost around $566 billion. Suddenly a $1 billion cruise ship does not sound all that expensive. Speaking of big ships, consider the world’s largest cruise ships, lined up in this infographic.