Four new venues are set to be added to Marella Discovery 2 this month as the cruise line transforms it into an adult-only cruise ship .

As of November, Marella Discovery 2 has joined Marella Explorer 2 as a dedicated adult-only vessel.

The former kids' spaces on the ship are now being transformed into new venues for adult passengers to enjoy and will be open on board from the new year.

Marella Discovery 2's climbing wall will remain on the ship but will be modernised with a wider variety of hold sizes, and will reflect the style of modern climbing centres and Olympic-standard walls.

Chris Hackney, chief executive of Marella Cruises , said the move to a second adult-only ship was based on guest feedback.

It follows research by Marella Cruises which found that 80 per cent of guests who sailed on Marella Explorer 2 , the line's other adult-only ship, said its adult-only status was the reason for booking.

He told The Independent: “Our core demographic is age 45-plus.

“A lot of these guests are at the life…