Last month, outdoor education centre Aberglaslyn Hall closed its doors for the final time.
It was the victim of cuts by Leicestershire County Council, which said it could no longer afford the £57 annual cost of running it.
Campaigners who fought unsuccessfully to save the hall in Snowdonia have now collected a series of reminisces and photos from the thousands of children who passed through its doors in the past 50 years.
Dr Roy Loveday, from the Friends of Aberglaslyn Hall group, said: "It was a very sad day when the hall closed.
"We understand the council needs to save money but, in our view, the value of the place is far greater than the cost of running it.
"It was a place of so many memories for so many young people over the years and we did not want to let its closure pass without taking the chance to look back.
"We have collected some great pictures of the place and spoken to people who recalled wonderful times spent there.
"We want the staff to know how much they were appreciated by all the people they looked after, some of whom had been away from home on their own for the first time."
One person who stayed at Abgerglaslyn as a youngster told the Mercury: "Those happy memories are still with me as an adult.
"There aren't many amazing places that create memories for normal, regular people – Aberglaslyn is one of these places, a jewel in the crown."
Another youngster said: "I vividly remember watching a member of staff at Aberglaslyn coax a crying boy of perhaps ten to abseil over the edge of some rocks.
"The transformation from 'scared and can't' to 'elated and can' is a big part of what children gained from the Aberglaslyn experience."
Another youngster, who attended the hall several times during the 1960s while a pupil of Market Harborough Grammar School, said the experience had "turned the boy into a young man".
County Hall yesterday revealed Aberglaslyn, set within 48 acres of estate, had gone on sale for about £750,000. It is being marketed as an outdoor education centre with accommodation for 38 visitors.
