Royal Caribbean has posted a spectacular video shot aboard Harmony of the Seas. Actually, it was shot from atop the giant ship, someplace you'd never normally go. The really cool part is that it was shot in 360-degree video, meaning you can put your mouse on the video and drag it around to see in any direction.
Look to one side and you can see Marseilles (France). Drag the picture around (Careful! You're on top of the ship.) to look off the other side of the ship, and you'll see the Mediterranean. Look behind you (yes, you can look down too - if you dare), and you'll see the ship below you with all its features.
You're going to need to play this several times to see everything.