In 1795 the school moved to what is now Westminster Bridge Road, and in 1852 relocated to Clapham, where it remained until the Rickmansworth Park site, purchased from Viscountess Bonnington for £61,500 in 1926, was formally opened by Queen Mary on 27 June 1934.
But this is not just an educational establishment of bricks and mortar surrounded by magnificent parks, but has what headmistress Mrs Diana Rose calls 'an inclusive ethos.'
Mrs Rose explains: "We encourage all the girls to do their personal best and not compete against each other. At RMS the girls learn to be tolerant, confident and poised, and these qualities stand them in very good stead."
Mrs Rose says that the education is broad based and not league table driven, but results compare very well with schools that are more selective in their intake. Not surprisingly, the school is heavily over-subscribed.
Today there are nearly 800 girls at the school, covering the pre-preparatory stage at four years up to sixth form level. Girls are not required to have a Masonic family connection, but all applicants have to pass the entrance examinations. However, there are approximately 40 beneficiaries of the Royal Masonic Trust for Girls and Boys.
Six Foundation Scholarships are available for daughters of Freemasons.
These are based on potential and achievement at 11+ for seven years, and are for boarding pupils only (see box).
Other scholarships - not requiring a Masonic connection - are also available at the school including music.
Mrs Rose says the RMS is particularly anxious to promote Foundation Scholarships. "We do not get enough applicants" she explains.
As educational facilities go, the RMS must rank among the best schools in Britain. From the science block, to the sports hall, swimming pool, information technology, library, planetarium, observatory and music, here is an educational establishment that excels.
From the magnificent chapel to the Great Hall, the cloisters and the classroom area - stretching for an eighth of a mile - to the huge dining area and the accommodation for boarders, all surrounded by hundreds of trees (one dating to 1691), there is here more of a university campus atmosphere than that of a school at the primary and secondary stage.
On the question of the school's ethos, there is a strong attachment between the girls and the school when they leave.
A House magazine, Machio, keeps the Old Girls in touch.
Web site created by Mark Griffin