Ditch the winter gloom and hit the beach in these sunny holiday destinations 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 The dark days of winter are the ultimate time for travellers craving a dose of vitamin D. While prices have surged for long-haul holidays, mid-