A college has banned swimming in a stretch of the River Cam that has been popular for bathers for centuries and where the writers Virginia Woolf and Rupert Brooke went skinny-dipping. King’s College Cambridge, which owns Grantchester Meadows, a riverside beauty spot south of Cambridge, erected a noticeboard on Thursday that also bans camping and launching boats from the banks. By Friday lunchtime, within a day of it launching, a petition against the ban on access to the water had been signed by more than 8,000 people. Signatories including Robert Macfarlane, the award-winning writer and fellow of Emmanuel College. Macfarlane, who is also a patron of the Outdoor Swimming Society, tweeted: “Terrible decision. The river here has been used by the community for centuries. There has to be a better solution.” The petition said: “Closing off use of the river along this stretch will shut down traditions dear to the people of Cambridge, and choke our connection with its beautiful natural surroundings. The closure would deny new generations the sense of wellbeing and enjoyment derived from the river at the only accessible spot where you can swim away from traffic and infrastructure.” King’s College said it was imposing the ban “reluctantly” after consultation with local councils, but said it was necessary to prevent dangerous, drunken and antisocial swimming and boating parties. The Grantchester Meadows have been a celebrated place for swimming for at least 500 years and includes Byron’s pool, the poet’s favourite swimming spot. In the early 1900s, the poet Rupert Brooke and his Cambridge neo-pagan set including Virginia Woolf regularly swam naked in the Cam at Grantchester. Woolf described the odour of bathing in the Cam as like “mint and mud”. More recently, bathing and boating parties have become a source of friction between students and local residents, according to King’s. In a statement, the college said: “Unfortunately, Grantchester Meadows has become a frequent site for large gatherings of individuals entering the River Cam under the influence of alcohol and other drugs, and subsequently requiring emergency medical assistance … As such it would be irresponsible for the college to continue to encourage swimming in an area where it is unsafe to do so.” It added: “We fully appreciate that swimming in the Cam is a popular activity and has numerous benefits for physical and mental health. The college has no desire to prevent anyone from sensibly exercising their right to swim in the Cam, or to navigate the Cam by kayak, punt or other vessel – indeed, we wholeheartedly wish that the Meadows will be used and enjoyed respectfully by all. “Nevertheless, we cannot in good conscience give our consent to these activities continuing as they currently are, with the evident dangers they pose to life, the consequences they have for others’ use of the Meadows, and the damage they are causing to the physical integrity of the land.” Lucy Nethsingha, the Lib Dem leader of Cambridgeshire country council, tweeted that she did not want a ban on swimming at Grantchester and was keen to find a “sensible solution to the difficult management issues in this beautiful area”.