An air ambulance landed on the front lawn of Alton Towers after a guest became unwell while on a rollercoaster.
Thrill-seekers were reportedly told to stay away from the grass area at the theme park while the helicopter landed.
Alton Towers confirmed a visitor to the park became 'unwell' on the ride Th13teen.
She was taken to the Royal Stoke University Hospital .
The rollercoaster was shut for a short time before reopening.
A spokesman said: "The air ambulance was called to provide medical assistance to a guest who had fallen ill during their visit.
"This is common practice when support is requested. We would like to reassure our guests that this was unrelated to any of our rides or attractions."
One ambulance, a senior paramedic, a paramedic officer, the Midlands Air Ambulance and a Community First Responder attended the scene.
A West Midlands Ambulance Service spokesman said: "We were called to reports of an unwell patient at Alton Towers at 1.57pm this afternoon.
"On arrival, crews discovered one patient, a woman. Following treatment at the scene for a medical condition, the patient was transported to Royal Stoke University Hospital by land ambulance."
Thirteen, which opened in 2010, was the world's first vertical free fall drop rollercoaster.
Guests on the ride plunge five metres in pitch black darkness.
The coaster, which replaced the Corkscrew, cost £15m to build.