It’s one of our favourite children’s books.

If you’ve never heard the tale of The Gruffalo, get yourself down to Waterstones on St Patrick’s Street on Saturday, March 23rd.

The much loved rhyming story of a tiny mouse with a very big imagination and a large monster with no confidence turns 20 this year.

The bestseller was published in 1999 by playwright Julia Donaldson and illustrator Axel Scheffler and Waterstones is celebrating with a special storytelling session at 12pm.

Gruffalo related colouring and activities will take place throughout the day and you can pick up your own copy of the book, which has sold 13 million copies worldwide, to read at home.

Costumes are not mandatory, but enthusiastically appreciated – especially if you’re bringing the kids. Check out the details here.