How skimpy outfits caused scandal at the Serpentine

To Londoners, the Serpentine is an oasis of calm where the raciest feature is the fleet of rowing boats. But some 70 years ago the lake was a hot-bed of raunchy impropriety, according to Scotland Yard.

A Metropolitan Police file unearthed at the National Archives in Kew, west London, has revealed considerable disquiet among police about the conduct of bathers at the pool in Hyde Park in the early 1930s.

As guardians of the capital's moral well-being, the Yard asked for extra officers and for a fence to be erection to combat a series of abuses, including "women of doubtful character" who "display themselves in flimsy bathing dresses".

The memo from an anonymous superintendent complains that the arrival of the women between 4pm and 8pm on summer evenings attracts "vulgar" men and teenage boys to the lido's mixed-bathing area.

The file adds that some upstanding female bathers had complained of their costumes being ripped off on diving boards and in the water by the over-excited male populace.

But chief among the concerns of the Yard, which was also combating an outbreak of bicycle thefts at the lake, was the new habit of male bathers to flout a by-law which stated that they should wear an all-in-one costume "fastened at the shoulder".

The memo, written before the opening of summer bathing in 1934, said: "The practice of many bathers on sunny days of rolling the costume down to the waist can only be overcome by considerable activity on the part of the constable on duty, in patrolling the area and directing such bathers to wear the costume correctly. This direction is very often received with bad grace and sometimes with opposition."

The document puts down much of the misbehaviour to the removal two years earlier of railings that had previously segregated users of a paid-for swimming area from the hoi polloi.

It noted that hundreds of bathers, including "men of an undesirable type" evaded the charge by undressing in the free swimming area, packing their clothes into an attaché case, and walking to the paying zone.

Subsequent over-crowding had the effect of "keeping away many decent-minded women who strongly resent the vulgar gaze of men and boys".

The file states that during one particularly riotous Sunday of bathing in the summer of 1932, 11 officers had to be dispatched to restore public order.

In order to prevent a repeat of such conduct, the superintendent asked for four extra constables to police the lido and for the fencing to be restored.

He stated: "As the result of prolonged observation, the conclusion arrived at is that, if the spectators were kept away from the bathing area as described above, much of the undesirable conduct would automatically cease."

Sadly for the Yard - and happily for the riotous bathers - the Ministry of Works, the government department responsible for the lido, did not agree. A letter in the file, published as part of an initiative to increase awareness of public archives, stated that there was no case for changing the regulations.

The incident was not the last time that Whitehall expressed concern at topless bathing in the Serpentine. Thirty years later, in the summer of 1964, the Home Office was alarmed at the prospect of female bathers shedding their bikini tops.

One memo read: "The parliamentary secretary feels it can only be a matter of time before the first topless bathing suit makes its appearance at the Serpentine lido. He would be glad to know that attendants there have been fully briefed to deal with such a situation when it arises."