A protest was held at Hampstead Heath on Saturday over the City of London Corporation's policy of allowing transgender women to use the Kenwood Ladies' Pond.
A City of London Corporation spokesperson said its policy ensures its public services "do not discriminate against trans people".
Campaigner and protest organiser Venice Allan said: “Women came together to reclaim our beloved Ladies' Pond on Hampstead Heath in time for the centenary in 2025. Plans are already being made for future actions.”
At the protest, speeches were made at the Stone of Free Speech, in Parliament Hill, by people including Muslim Public Affairs Committee UK member Catherine Heseltine and Maya Forstater of Sex Matters.
Organisers claimed more than 150 people attended.
A spokesperson for the City of London Corporation, which manages Hampstead Heath as a registered charity, said before the protest: “We do not tolerate any form of discrimination.
“Our gender identity policy ensures our public services do not discriminate against trans people.
“We welcome a wide range of service users and we want to ensure they all feel comfortable accessing and enjoying the bathing ponds and other facilities.
“All communities should be fully respected.
“We aspire to be a leader in diversity, equality and inclusion, and we are committed to supporting a strong, sustainable and cohesive society in the capital and beyond.”
The Kenwood Ladies' Pond Association said: "The KLPA was not involved in the recent demonstration at the Ladies' Pond.
"The City of London manages all the Hampstead Heath bathing ponds and decides the policy around access for transgender swimmers in accordance with the Equality Act.
"More than four years ago the KLPA engaged in a lengthy consultative process and debate, with members subsequently agreeing to maintain their support for the city's policy of gender self identification. Neither position has changed. The KLPA will continue to listen to the views of our members on matters related to the Ladies' Pond.
"A primary concern is preserving the pond's special atmosphere, which is joyful, welcoming and peaceful. The pond is primarily a place to swim and relax, treasured by many women and girls. We encourage all swimmers to respect the space staff and each other."
Green Party London Assembly member and councillor for Highgate Sian Berry said on Twitter the protest "doesn’t reflect the loving and inclusive values of the people in Camden at all".
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here