The pit has held open weekends since the mid-1990s, and they have proved to be hugely popular events.
Unfortunately, due to Covid restrictions, no event took place last year and organisers were not sure whether anything could go ahead this year.
But members of the Friends of Pleasley Pit made the decision to have an open day - and it seems to have paid off.
Walter Edson, aged 74, group chairman, said: “It was a brilliant day and I think we had about 600 people coming in.
“We’d been unsure as to whether we could go ahead, but we made the decision early doors and it seems to have worked well.
“I actually think it was one of the best days we’ve had.”
A retired maintenance engineer, Walter’s association with the pit goes back to 1966, when it was working.
Closed in 1986, it is now a volunteer-led mining museum.
The site has been restored over many years to preserve it for generations to come.
Posting on their Facebook page after the fun day, the Pleasley Pit Trust said: “Thanks to every single one of you who came and supported us.
“It means so much to us that you all showed up bigger and better than ever after Covid. We hope you all had a lovely day.”
Alex Ivanov visited the open day with family.
He said: “I cycle to Pleasley Pit quite a bit, a couple of times a week and sit by the pond, feed the birds and relax – it's been my place to escape daily stress.
“So, when I saw that they had an open day, I thought it'd be a good chance to take the kids and see engines and the museum.
“It was a great day. It was the first time we've been inside the building and seen the engines running. There were lots of mining relics and artefacts on display,and the Pleasley Colliery Brass Band was great.
“We had food and drink from the cafe, ice cream from the van and the day was topped off by the Battle of Britain Memorial Flight Dakota flypast. It was a good family day out.”