For the 32 years of its existence, Alton Towers has had a very simple system to decide who can try its scariest rides. Not 140cm? Then no loop-the-loop, it's back to the spinning teacups for you.
"We do get some on their tiptoes," said Carla Woolridge, who has worked at the park for five years. "We have to send them away to come back when they've grown." Now, she and her colleagues face a new challenge with the unveiling of the first ride in Britain to be subject to an age rating from the British Board of Film Classification (BBFC).
Just as the cashier at the off-licence must decide whether that layer of makeup masks a 16-year-old visage, so too must Alton Towers staff now judge whether those lining up to ride Nemesis Sub-Terra without their parents are 12 or over, after the BBFC suggested the theme park slap a 12A rating on the new attraction.
According to BBFC guidelines, 12A allows for "moderate physical and psychological threat, provided disturbing sequences are not frequent or sustained".
Phoebe Hill and Olivia Grocott remember how frustrating it was being that little bit too small for the best rides at Alton Towers. "I think I was 10 before I was tall enough," said Olivia with a worldweariness that suggested she was harking back to a bygone era, rather than 2009. The girls go to Cheadle Academy, which is so close to Towers, as the locals call it, that they have lost count of the number of times they've been.
They agreed it would be "very annoying" to queue up for ages only to be turned back because they looked underage (neither carries ID; why would they?). In 2010, Olivia waited for two hours to ride Thirteen, the first vertical-drop rollercoaster in the park. On Friday the 13-year-olds became the first children to ride the much-hyped Nemesis Sub-Terra, which opens to the public on Saturday.
Chosen by their school for having the most achievement points in Year 8, the girls were giggly with excitement. They were greeted at the entrance to the ride by grim-faced men in black paramilitary uniform, billed as members of the shadowy Phalanx, who barked orders at the girls and hurried them into a lift.
When the doors opened, they were in a dark chamber, like a cross between the Red Dwarf spaceship and the Industrial Zone from the Crystal Maze. In the middle was a glistening egg the colour of molten lava. Computer screens showed a scan suggesting the egg looked ready to hatch. Olivia seemed nervous.
The girls were strapped into seats with overhead restraints. Suddenly the lights were out and the floor fell away. Olivia screamed. To say any more would ruin the fun, but data collected by Paul Tennent, a scientist from Nottingham University working for Alton Towers' Thrill Laboratory, shows that Olivia's heart rate shot up from 62 beats a minute to 213, the highest Tennent has recorded so far on the ride.
Phoebe's heart peaked at a cool 153. Not a surprise to those who could hear her laughing throughout. Afterwards, the girls reflected on their experience. "It was a bit boring, it didn't really do much," said a nonchalant Phoebe. Olivia, though admitting she was scared, thought that at 2.5 minutes it was "too short – when it finished I was a bit like, was that it?"
They both preferred the other new ride for 2012, Ice Age: The 4D Experience, which has no height or age restrictions. "It was funnier," said Phoebe. "And longer."
