Secret spaces: The ultimate bonus rooms on board luxury superyachts

The Neptune Lounge on board the 74.5-metre Elandess is modelled on the Nemo Room of the 83.5-metre Feadship Savannah, but with even larger viewing points. The Neptune Lounge provides a relaxing area to observe the views above and below the waterline; it's part grotto, part submarine and part amphitheatre. The space is constructed with three-metre-high ceilings and near full-height glass, which is 10 centimetres thick, with one-third of the windows below the waterline. To make the atmosphere suitably aquatic, the floors and ceilings are painted blue with soft furnishings matching in colour.

The 83.5-metre Feadship superyacht Savannah features a semi-submerged viewing lounge, named the Nemo lounge. It could have gone anywhere in front of the propellers, but its location links it to the pool deck and to the swim platform, where a complex hatch in the aft stairs provides secondary access. Guests relaxing in this area are treated to unique views and can enjoy the sunset at the same time as watching fish swimming beneath the surface.

The 47.6-metre Candies Shipbuilders yacht Mystere Shadow is more than your typical superyacht support vessel. Sure, she can carry submarines, motorcycles, cars and helicopters for the mothership, but after a redesign by Pastrovich Studio, she’s pretty luxe in her own right, with a pool, spa area and her own bonus room: a disco. Sans toys, Mystere Shadow’s hangar becomes a full-on nightclub with laser lights, smoke machine and, of course, a disco ball.

Who says you have to wait until the kids are grown up to take the voyage around the world? Certainly not the owners of sailing yacht Vertigo who put this classroom to good use while travelling with their young family. Outfitting the yacht with a classroom and bringing along a tutor meant the kids could keep up with studies while they sailed. This bonus room on the award-winning sailing superyacht Vertigo has desks and a SMART board — an interactive whiteboard hooked up to the computer that utilises touch recognition.