Cycling fans barred from summit of the London 2012 Road Race

Dress rehearsal is overshadowed as Games chiefs are criticised over Box Hill route

Mark Cavendish , fresh from his green-jersey triumph at the Tour de France, will lead the British team tomorrow in a test race for the 2012 Olympic cycling road race.

Click HERE to upload graphic - The Battle of Box Hill (276.05kB)

But a row between London's Olympic organisers and cycling fans looks set to sour the event.

Elite cyclists will ride the Olympics route, starting and finishing on The Mall in London through Hampton Court Palace. In Surrey, the course takes in two laps of Box Hill, a focal point of the race and a climb relished every Sunday by scores of amateur cyclists. But unlike the Tour de France, where thousands of fans are free to line the route and get up close to the riders, many fans will not be able to cheer the cyclists as they tackle the hill tomorrow, or at the Olympics next year.

"Keep out" signs and large metal fences have appeared in the areas surrounding the hill, and access to the best vantage point and the steepest part of the race – the "Zig-Zag Road" – is restricted.

The restrictions stem from Box Hill's status as a Site of Special Scientific Interest ( SSSI). The discovery of a species of butterfly and the protection of orchids in the area have led Natural England, the government's adviser on the natural environment, to impose limits on the numbers of people allowed there.

Cycling fans have criticised Locog for not checking this with landowners before planning the route, leaving many fans disappointed that they will be excluded from the best part of the race. Just 3,400 wristband holders will be allowed inside a specially constructed enclosure. "In Europe, at events like the Tour de France, you just turn up and stand at the side of the road all day and watch the race," said Simon Richardson, deputy editor of Cycling Weekly.

"The road race is always the big free event at the Olympics," he added. "Box Hill is the main part, and they've restricted it. Lots of people who have missed out on tickets can't go and watch in the prime spot. The Olympic Road Race, the event that offers the first medal of the Games in 2012, could set a tone of exclusion and resentment."

Locog said that only a small part of Box Hill would be restricted, and that efforts have been made to ensure these seats go to cycling fans. An allocation of tickets will be distributed through cycling magazines and through the British Cycling – the national governing body for the sport.

A spokesperson said: "The 140km route is a challenging route which will produce an exciting race for spectators to watch for free. One area in Box Hill, specifically the Zig Zag Road, will have restricted access as it is heavily protected by the National Trust. The wider Box Hill area will have spectator access. We encourage people to watch this [weekend's] great international sporting event which is a dress rehearsal for the 2012 Games."

Locog faced similar criticism in June following a decision to fence off a public park which will have a view of Olympic sailing events next year. In June Locog applied for planning permission to fence off Nothe Gardens in Weymouth, Dorset, where it would charge for tickets.

If approved, the plan would close off 40,000 square metres of public space. Locog claimed the plan would aid "safety and crowd control". But that was branded "nonsense" by local councillor John Birtwistle.

He said: "The bottom line is that they are trying to make Olympic sailing a pay-per-view event in Weymouth."