But on the morning the park reopened its doors, it was confirmed that 17-year-old victim Leah Washington has had her leg amputated above the knee due to her injuries.
The youngest seriously injured victim was on her first date with Joe Pugh, 18, who broke both his legs in the incident.
In a statement, Leah’s father David said: ‘Leah has suffered a life-changing injury and now has many months of rehabilitation ahead of her.
‘We have done this to put people's minds at rest and we would also ask everyone to respect Leah's privacy as she undergoes this rehabilitation.
‘We would like to thank all the emergency services at the scene and all the hospital staff who saved Leah's life.’
Two other victims - Vicky Balch, 20, and her boyfriend Daniel Thorpe, 27 - remain in hospital with serious injuries.
Two carriages on the park’s Smiler ride collided last Tuesday afternoon - injuring dozens and leaving four young people in a serious condition.
Since the incident, the park had been shut as investigations are carried out.
On Sunday evening, the park announced that they would reopen at 10am on Monday 8th June.
However, despite being open to the public, Smiler, Oblivion, Enterprise, Sonic Spinball and Nemesis Sub-Terra, will all remain shut as they implement additional safety procedures.
Chief Executive of Merlin Entertainments, who own AT, said: ‘We are very aware of the impact it will have on those involved and we are all doing all we can to provide out support to those injured and their families.’
‘We closed the park immediately whilst preliminary investigations took place and to give our staff time to come to terms with the accident.’
On Sunday, Victoria Balch, who suffered ‘life changing’ injuries in the crash, underwent further surgery - a day after she marked her 20th birthday.