More than 1,000 athletes are bracing themselves for the 33rd edition of the Round Norfolk Relay this weekend.
The event, which is sponsored by officescape, has grown from 22 teams in 1988 to 60 teams this year for the 198-mile continuous run made up of 17 separate multi-terrain stages, starting and finishing at the Lynnsport complex in King's Lynn.
Teams depart in staggered starts from 5.30am to midday on Saturday and eventually finish around 10am on Sunday, assuming their pre-race time estimates are accurate.
The circular route, some of it off-road on sand and loose shingle, follows the coast round to Great Yarmouth, before heading back west along the county boundary to Thetford and Downham Market before arriving back in King's Lynn in time for breakfast.
The runners are assisted by back up crews comprising cyclists, time keepers and drivers. Many of the teams provide marshals on the course.
It provides an ultimate club challenge and a great team spirit, rewarding both individual and team achievements.
This year's 60 teams are from 45 different clubs of which 13 have run the event more than 20 times.
Last year's race had 1,020 competing runners of which 364 (36 percent) were ladies and 656 (64 percent) men.
The number of "masters" competing (ladies over 35 and men over 40) was 714 (70 percent). Youngest runner was 15 years and the oldest runner was 78 years (Eva Osbourne of Wymondham AC).
Over the past 32 years 6,800 runners have taken part, of which 3,600 runners have done so more than once.
King's Lynn and Downham Market based Ryston Runners, who ran the first race solo as a trial run in 1987, will be competing for the 33rd time, closely followed by Norwich Road Runners with 31 appearances. While East Anglian teams dominate the field, regular visitors from as far afield as Bishop's Stortford, Wellingborough and London are back again and for Paddock Wood it will be their 21st appearance.
MORE: Love running? Join the Run Anglia Facebook group hereWhile the ultimate prize is to be the quickest team round the county boundary, there are a host of other categories to be won.
Such is the affection in which the event is held that individuals cherish the 10 and 20 year mementos given out.
Some prefer to pit themselves against their previous stage time while for a few others the aim is to compete all 17 stages over the years.
Ryston Runners chairman Robert Simmonds will receive his 20th appearance medal.
Individually, Richard Sales of Norwich Road Runners (NRR) will be making his 22nd consecutive appearance and his 29th running of the event. Fellow NRR, Ray Lindsey, will be making his 26th appearance.
Neville Baker, of Headington Runners, has run 22 times and is the only runner to have completed all 17 legs in different years.
In 2018 City Of Norwich AC were convincing winners in a fast time of 20 hours 43 minutes and 22 seconds which is an average of 6 minutes and 18 seconds per mile for 198 miles.
This year they will face stiff competition from recent past winners Cambridge and Coleridge AC and Ely AC, as well as local clubs NRR and Ryston Runners.
For the first time ever a wheelchair athlete will join Cambridge and Coleridge on leg seven, which is 9.24 miles from Mundesley to Lessingham.
For many years the runners in several legs battled against some tough weather conditions, leaving all eyes glued to the forecast for this weekend.
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