Merseytravel is organising another walk through the Queensway Tunnel to celebrate its 75th anniversary and raise cash for charity.
Last year, nearly 15,000 people took part in the 2.13-mile walk as part of Merseytravel’s contribution to the Capital of Culture celebrations.
This time, on Sunday July 19, Merseytravel is donating money raised through ticket sales from “Under and Over the Mersey” 2009 to Claire House children’s hospice, which is its corporate charity for 2009.
Merseytravel says it would like to see as many walkers as possible to get out their fancy dress and sponsorship forms for their own favourite charity.
A spokesman said: "'Under and Over the Mersey 2009' will probably be the last chance for such a unique view of this engineering masterpiece for many a year so we’re making the walk even bigger and better, more colourful and just as memorable."
The event, which will be accessible to everyone, is hosted by Keith Chegwin and celebrities will count down the five planned walkthrough processions.
There will also be vintage cars, carnival rides, musical entertainment and dramatic circus performances.
Walkers can travel free back to Liverpool on a Mersey Ferry – with all three boats on the River for the day – and everyone taking part receives a commemorative medal.
Everyone also gets a wristband, which entitles them to two-for-one entry to Spaceport, The U-boat Story and Mersey Tunnel Tours until August 16.
Single tickets for "Under and Over the Mersey" cost £5 and family tickets (two adults and two children) are £15.
You can book online at www.merseytravel.gov.uk or at any Merseytravel Centre or more information call the Merseytravel information line on 0151 330 1702.