The event, which took place just days ahead of its permanent closure due to the secondary schools merger in Whitby, proved massively popular, with people queuing from the main entrance to the tennis courts to get in.
The school put on a huge display of archive material, from its opening through to the present era, with photos of form classes, sports pictures, press cuttings and much more.
Fittingly, this included the successful battle to save Eskdale from closure in 2016.
Head Phil Nicholson said: “It was some turn-out! We reckon around 500 people came through the doors.
“It was lovely to be able to give so many ex-pupils and staff the opportunity to reminisce about yesteryear and see some old school friends.
"I enjoyed walking around the school listening to tales about the freezing swimming pool, the plays that were performed and the day Geoff Boycott came to the school.
"It showed how special Eskdale is to so many people.”
Former teaching assistant Jane Westwood posted on the Eskdale School Memories page on Facebook: “Thank you so much to everyone who came to look around Eskdale School.
“Looking around, it was great to see people catching up and reminiscing.”
Elena Bloor, whose dad Ian Bloor has taught at Eskdale since 2001, helped put the exhibition together.
The 21-year-old said: “There are a lot of people who wanted to come tonight but couldn’t, whether they were from the 50s or ex-teachers..
“We’re hoping it will go to a museum.”
Among those enjoying the exhibition was Ann Trencher (nee Page), who attended the school in 1954.
“It’s been lovely,” she said. “I recognise some of the old class photos.
“I’ll be sad to see the school close - when I was here it was all new.”
Margaret Wardell, nee Beeforth, was 14 when she attended Eskdale in its first ever year and said the celebration event was “bloomin’ marvellous” while her daughter Jane Wardell, who attended 1971-73 and now lives in Doncaster, praised the fantastic response from the community and added: “I thought I’d regret it if I didn’t come and I’m pleased I did.”
Eskdale closes this summer and Whitby School, created from the merger with Caedmon College, will open in September.
9. Whitby's Eskdale School 70 years of memories
Mum and son visit the school. Photo: Richard Ponter
10. Whitby's Eskdale School 70 years of memories
Terri-Anne Jones with the Eskdale School cake pic. Photo: Richard Ponter
11. Whitby's Eskdale School 70 years of memories
Remembering the Eskdale Bear. Photo: Richard Ponter
12. Whitby's Eskdale School 70 years of memories
People enjoying looking at the archive pictures. Photo: Richard Ponter