National Unicorn Day is really here!Published9 April 2022Image source, Getty ImagesImage caption, 9 April is National Unicorn day. It's a chance for fans of the mythical creatures to celebrate by making rainbow cupcakes and decorating them with lots of sprinkles and glitter. Stories of unicorns have been around for thousands of years. Here's what we know about these mysterious creatures.Image source, NATURE ECOLOGY AND EVOLUTIONImage caption, What鈥檚 four metres long, 2.5 metres high, weighs 3.5 tonnes and has a very big horn in the middle of its face? A really massive Siberian unicorn, that鈥檚 what. Researchers at the Natural History Museum say 'Siberian unicorns' were around before the Ice Age and lived at the same time as early humans around 35,000 years ago. As you can see it wasn't all rainbows and sparkles for this unicorn; the species is an ancestor of the modern-day rhinoceros, but was much bigger and heavier.Image source, Getty ImagesImage caption, This is the classic image of a unicorn. It's not as big or hairy as the Siberian unicorn - but have you ever wondered why the animals are so popular? Chances are, you've probably seen someone with a unicorn related item like a bag, jumper, or fancy-dress costume, or perhaps you're a big fan of the mystical creatures yourself!Image source, Getty ImagesImage caption, The mythological creatures are like horses, but the main difference is that they have a single spiral horn. This picture was taken at a winter solstice ceremony at Stonehenge in Wiltshire. The woman wearing the unicorn mask said she thought the imaginary creatures were beautiful.Image source, Getty ImagesImage caption, No-one knows where the idea of unicorns came from. Many people in the Middle Ages really believed that unicorn horns could heal sickness. However, many of the horns that were shown off as unicorn horns actually came from other creatures, like rhinos and also these animals - narwhals. These strange mammals look like unicorn whales! Narwhals are also known as the unicorns of the sea.Image source, Getty ImagesImage caption, Is this a picture of the Forbidden Forest? Unicorns were really important to one famous baddie - can you remember who? Lord Voldemort of course! In Harry Potter and the Philosopher's Stone, He Who Cannot Be Named needs to drink unicorn blood to stay alive. In the world of Harry Potter, killing a unicorn is seen as a terrible crime.Image source, Getty ImagesImage caption, Unicorn outfits are great for dressing-up parties and make pretty cool costumes. This chap is called Parker, and his owners gave him this unicorn horn for a Halloween Parade in the town of Sacramento in California. It's very cutesy, but not that spooky considering it's for Halloween!Image source, Getty ImagesImage caption, Meet ballet star Rainer Krenstetter! He dressed up as a unicorn during the Life Ball at City Hall in Vienna, Austria. Unicorns are often shown as pure white, but in stories they can be any colour - from jet-black and brown to dazzling gold, brilliant red or pink.More on this story'Unicorn dog' becoming very pup-ular social mediaPublished17 March 2020Are llamas the new unicorns?Published10 February 2019This 'unicorn' lived more recently than we thoughtPublished30 March 2016