The last time Illustrious threw down her gangway to the public three years ago, over 8000 people took the opportunity each day to go aboard.
With this city's strong links to the sea, ship visits - whether they're cruise liners or naval vessels - are always hugely popular.
When HMS Liverpool visited last year, around 9,000 people took the opportunity to board her, and as HMS Illustrious is one of the Royal Navy's extremely recognisable ships we're expecting thousands to flock to see it.
This visit gives us just a taste of what is to come in May when Liverpool becomes the focus of the national Battle of the Atlantic 70th commemorations when around 25 warships will take pride of place on the splendour of our magnificent waterfront."
Liverpool is a very special place for a ship such as HMS Illustrious to visit and we always receive a very warm welcome indeed.
"We hope to be able to reciprocate in some small way by opening our doors to the general public to visit on Saturday and Sunday and to meet some of our people for an insight into some of the things we do on board."
– CAPTAIN MARTIN CONNELL, COMMANDING OFFICER, HMS ILLUSTRIOUS