Led by the Labour MP AndrewBennett, about 50 of them defied Mr van Hoogstraten's obstructions on the public foot-path at his Framfield property by walking around them.
There were almost as many media representatives in attendance, plus a handful of police officers. But to their disappointment, there was no sign of Mr van Hoogstraten nor of any of his employees who have previously warned off ramblers.
Mr van Hoogstraten, 53, has said he regards ramblers as "scumbags" and that any who came on to his land would be "viciously dealt with". Yesterday, however, he did not return calls and was believed to be in France with his family.
The ramblers had informed him of their plans to traverse the public footpath, which runs for half a mile through his High Cross Estate and which has been blocked - they say illegally - for 10 years. A barn has been built across the path, a bridge over a stream has been removed and large steel refrigerator units have been used to form a barrier at the gate where the footpath begins.
But the walkers, led by Mr Bennett, who is the president of the Ramblers' Association and the joint chairman of theCommons Select Committee on the Environment, cut across on to the estate. They walked along the footpath, concluding by climbing over a barrier with a sign: "Private property - keep out". Despite a recent hip replacement, Mr Bennett obliged the photographers by climbing over the obstructed gate several times.
He said: "I wanted to see the route for myself and then talk to the Environment Secretary, John Prescott, about what action his department will take against this bully.
"He must not get away with blatant blocking of a public highway and intimidation of those who want to walk it. I am delighted the Ramblers' Association is taking legal action to have this path reopened."
He was accompanied by alocal rambler, Jack Dunn, 82, who reported the obstructions to East Sussex County Council 10 years ago. Mr Bennett said: "What's happening here is only the tip of the iceberg of footpath obstruction. Mr van Hoogstraten's involvement made it "a very prominent tip".
East Sussex County Councilis due to discuss the footpath issue on Monday. David Neighbour, a councillor who attended the march, said he had been worried about the safety of council officers because there had been reports that they have been threatened in the past by Mr van Hoogstraten's men. He said the council had not taken legal action against Mr van Hoogstraten because it was too costly.
The Government's hesitation about its promised right to roam over open countryside is to be highlighted by a Labour MP's private member's Bill.
Gordon Prentice, MP for Pendle, is to table a Bill next week proposing a legal right of access for walkers and ramblers to uncultivated land. It is likely to receive substantial support from backbench Labour MPs as a sign of their mounting disquiet at the Government's lack of action on a firm pre-election commitment.
The Government's proposals are still awaited seven months after the end of the public consultation exercise.
The consultation document was widely seen as a watering-down of the original right to roam commitment.
The right to roam has already been conceded north of the border.
This week's Scottish land reform proposals say that " a right of responsible access to land for informal recreation, on enclosed as well as on open and hill ground, should be enshrined in law".