They've been in Doncaster for more than 200 years.
They have had some of the most famous people in the borough among their membership.
But the borough's Freemasons reckons they've got a poor deal when it comes to image.
They are aware of their 'secret society' image and reckon that it's unfair.
And they're doing something about it.
They have just had their first open day for several years at the Masonic Hall on Priory Place, to unveil all their so-called 'secrets'.
Mason Stuart Grantham: "We've opened up the Masonic hall to the public. I don't think that's very secretive. We have a bookshop in London where people can buy books with details of all our so called 'secret' rituals. That's not really very secret at all.
"This idea of secrecy is now getting to be a bit frustrating, and that is the main reason why we opened up the masonic hall. We're thinking we may do it every year. Non masons come here often anyway to take part in functions."
He believes the 'secrecy' image comes from wartime. He says before World War Two the Doncaster masons would hold public processions and even go for picnics in Clumber Park. A picture hangs from the wall of the Masonic Hall of masons in full regalia at a function at the Mansion House in 1909.
However he added that it emerged during the war that Hitler was persecuting Freemasons, arresting and murdering them. As a result, they withdrew from the public gaze, a move which he thinks may have led to the reputation for secrecy.
He feels that the reputations has stuck, with some members now declined to reveal their membership because they feel it will be held against them. Stuart does not believes that is fair.
Ian Smith, a fellow Doncaster mason added: "Would a secret society have Masonic Hall written on their front door, with the symbols of the organisation, the set square and compass?"
Doncaster has around 300 masons, based across five lodges, all based at the Masonic Hall. The oldest, St George's Lodge, dates back to 1780, and originally met at the Red Lion on Market Place. The membership grew after World War One as troops returned from the war, with Don Valley Lodge (opening in 1919), Danecastre Lodge (1926), Hall Cross Lodge (1938) and de Maulay Lodge (1946).
Members wear their regalia, including an elaborate apron, at ceremonies in the main chamber, before heading downstairs to dine together in their lounge suits. They raise money for charity, much of which goes to causes in Doncaster.
They recently gave Doncaster Housing for Young People a £5,000 grant for a counselling service for young people, which will pay for it to continue for another 12 months. Other recipients of donations have been £2,500 for Arksey Primary School for an outdoor canopy for outside learning, and £750 for Hickleton Harriers junior football club, for new kits.
Ian, a retired undertaker who has been a mason since he was aged 24, said masons rules forbid members using their positions to provide unfair advantages to other members. If they did, they could be expelled. He said Freemasonry promotes character development, good moral conduct and fairness in all things.
Entering the hall in Doncaster, which opened in 1915, a staircase lined with black and white pictures of former grand masters from days gone by leads to the first floor. The first floor houses the bar and dining room. Another flight of steps leads to an anteroom, lined with more pictures of the organisations officials. It also includes pictures of King Edward VII and King George VI in their masonic regalia.
That leads to the Lodge Room. It has a black and white checked carpet, the checks representing good days and bad days. Four tassles are placed in each corner, representing prudence, temperance, fortitude and justice. It is here where rituals are carried out like swearings-in of officials. One of those does include a rolled up trouser leg - to symbolise that a prospective member is a free man with no marks of imprisonment such as a ball and chain on his leg.
Paintings hang on the wall symbolic of birth, entering work, and judgement day. Boards carry the names of former grand masters, dating back hundreds of years, and records of members are held dating back to 1780.
They include the organist and composer Edward Miller, and the baronet Sir Brian Cooke, who lived at Wheatley Hall. Former mayors were also members.
The room drips with history. Documents dating back to the 18th century are framed on the walls, and a ceremonial mason's plumb line which was used to lay the foundations of Christ Church, Thorne Road, in 1828 is on exhibition.
Stuart, a retired wholesale fish merchant who has been a mason since the 80s, was pleased with the open day. "We got dozens of people visiting, and the civic mayor visited. We event had some people asking how you join.
"People were really pleased to be able to come in and look around, and see that we have nothing to hide."