Where better to learn to dive than in the crystal-clear lagoons of French Polynesia? Scuba courses are available on Paul Gauguin Cruises’ eponymous ship,  even for those with no experience, and there’s a good chance of spotting several different kinds of shark, as well as moray eels, sea turtles, barracuda and all manner of dazzling tropical fish, flitting in and out of the coral.

The legendary Jean-Michel Cousteau, son of Jacques and one of the world’s best-known marine conservationists, joins several cruises a year.

  • From £5,202 including flights, one night in Los Angeles and seven nights on board, including drinks and tips (020 7399 7691, pgcruises.com).