A mother and son from Kent were left horrified after visiting Pontins Holiday Park in Camber Sands, East Sussex.
Tierney Hinde, 28, went to the resort with her son Presley who is just four.
Although the pair paid £500 and planned to stay at the park for a week, they ended up leaving after just three days thanks to the disgusting conditions of the apartment they were given, the Daily Mail reports.
Tierney was looking forward to her first trip away with her son, who is autistic, but was shocked by the dirty sheets they came across in the first apartment.
She was then offered a room on a higher floor as an alternative but the problems only worsened when they entered their replacement apartment to find what appeared to be bloody spattered on the windows.
The young mother said: "It was supposed to be the first trip with my son but it was a farce that's all I can say.
She added: "I nearly cried. I don't really get like that but it was just a complete waste of time."
Tierney says she had chosen Pontins over Butlins and Haven because the doors have locks which allow her to monitor Presley and keep him safe as he has a tendency to disappear, reports Kent Online.
When they were moved to the room on the higher level Tierney was also concerned this might prove problematic for Presley who has poor co-ordination and little sense of danger.
Her fears were confirmed when he fell down the steps on the landing.
Miss Hinde said she was also disappointed by the activities on offer to the kids, saying: "Pontins should be getting involved with all of the kids and it wasn't like that at all. All he wanted to do was go towards the arcades because there was nothing else for him.
"I went there when I was 15 and nothing had changed since then and they were supposed to have had a rebirth in 2011."
Tierney was offered 50 per cent off vouchers and VIP treatment for her next visit but she has said she won't be going back to the resort.
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