Fortress security for GM wheat trial
Past two barriers of security, a mile inside the Rothamsted Research centre, I was taken to see what must be the most closely guarded field in the United Kingdom.
With groups of police and security guards dotting the lanes throughout this centre, a relatively small plot of land lies behind high steel fencing.
This is where genetically modified wheat is being grown, part of an experiment to see if the plants can repel a common pest, aphids, without having to resort to insecticide.
One of a small group of journalists, I was allowed through the fencing into the plot itself - this is crop science conducted inside a fortress.
Under a blazing sun, the earth was baked dry, and the GM wheat, a pale green, twitched and fluttered in the breeze.
The wheat is being cultivated in small squares, surrounded by other plants which will be checked to see if they are contaminated by the wheat.
The plants themselves look unremarkable and it was a strange sensation making the visit under such stringent conditions.
Walkie-talkies crackled, a police helicopter hovered overhead and acres of day-glo clothing were apparent on the guards monitoring the perimeter.
The initiative to take journalists inside the trial site is part of a major PR offensive by the scientists and their backers to be open and transparent about the research - in an effort to explain its value to the public.
The director of the centre, Professor Maurice Moloney, has been giving endless interviews this morning to describe the work.
His appeal is simple: let us do the experiment to see if this technique makes sense.
For the community of plant scientists, and its supporters in government and the wider world of science, this is a vital test of strength.
The planned protest by anti-GM campaigners, Take the Flour Back, is gathering at the edge of the centre.
Their argument is that the risks of conducting GM trials in the open are too great and that the site should be "decontaminated".
No one can be sure how this will play out. I'm off to see the protestors now.