UK based boyband One Direction are today (April 18) celebrating their 1000 day anniversary of being a musical group.

The hashtag '#1000daysof1D' is currently the world's No.1 trending topic on social networking site Twitter and member Niall Horan took to his official account to express his excitement at the milestone:

"Wow! Thank you so much for your support! #1000daysof1d ! It's been amazing! Love you."

Singer Louis Tomlinson also weighed in and added: "1000 days of being in the band ? Wow that really is incredible :) Amazing that you guys have shaped our career! Thank you so much x"

Meanwhile, the lads are enjoying fame on an international level with a world tour to support their latest album and they have also just sat for staff at the famous Madame Tussauds waxwork museum, who have made some incredibly accurate figures of each star.

Their waxworks will be on display at the London location from today until July 19 when they will be shown at the museum in New York City.

Watch footage from Madame Tussauds' sculpting of Horan here: