A picture taken on April 21, 2016 shows the number 90 and the Queen Elizabeth projected on the Tower of Homage of the Moorish Castle in Gibraltar to mark her 90th birthday. Queen Elizabeth II is set to celebrate her 90th birthday on April 21, with a family gathering and a cake baked by a reality television star, as a new poll finds Britain's longest serving monarch is as popular as ever. The queen has reigned for more than 63 years and shows no sign of retiring, even if she has in recent years passed on some of her duties to the younger royals. / AFP PHOTO / JORGE GUERRERO