Cruise editor Marc Shoffman selects some of the best sailings to enjoy natural and man-made wonders in your lifetime Sign up to Simon Calder’s free travel email for expert advice and money-saving discounts Get Simon Calder’s Travel email Get Simon Calder’s Travel email Email * SIGN UP I would like to be emailed about offers, events and updates from The Independent. Read our Privacy notice M any keen travellers have a bucket list of trips or natural wonders to experience, and a cruise can be an