It attracts nearly 1,000 people every year – and is becoming increasingly popular with runners.
The Orwell Challenge takes place on June 21, 2020, and gives people the chance to walk or run along the beautiful Orwell estuary, over a variety of distances.
It will be the 44th year of the event, which has now raised £3million for good causes.
In recent years, the event has introduced a trail marathon and half marathon, which is validated by the Trail Running Association, affiliated to UK Athletics. That means runner results will be posted on RunBritain and the Power of 10 websites.
However, if you simply want to walk, there are options between three and 25 miles - with the routes well signposted and marshalled.
The challenge, organised by Ipswich East Rotary Club, was launched this week at Greshams Ipswich, where BBC Radio Suffolk's Mark Murphy said it was a very special event for the county.
He explained: "Anybody and everybody can take part and raise money for whatever cause they want. There are lots of other fundraising events but they are for specific charities - this is for absolutely everything."
Organiser John Button said they continued to refine the event each year and make improvements.
He added: "It is a challenge but it is so varied - people who do it really love it."
Entries are now open - visit the website to enter.
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