[5] After a construction time of 32 months, the ship first set sail on 15 May 2016 from the STX France docks in Saint-Nazaire, viewed by some 70,000 people.

[20] During these voyages, passengers complained of ongoing construction, a lack of hot water, unopened attractions, excessive waits at restaurants, and other issues.

[21] The ship's maiden voyage departed from Southampton on 29 May and arrived at its summer home port of Barcelona on 5 June.

[22] For the inaugural season, Harmony of the Seas offered seven-night western Mediterranean cruises originating from Barcelona and Civitavecchia.

LED and fluorescent lamps replace incandescent light bulbs, reducing power consumption and the need for air conditioning.