Casual swimming sessions at Sportspace Hemel Hempstead will be affected at the weekend as the centre hosts its annual Swimathon for Marie Curie Cancer Care.
The sessions on Friday evening from 6pm to 9pm, and Saturday from 1pm to 5pm will be cancelled as part of the nationwide fundraiser.
All lessons are as normal, but Sportspace apologises for any inconvenience caused.
It is still possible to sign up for the Marie Curie Swimathon at www.swimathon.org, but entry closes today, Wednesday.
If you are interested in volunteering on the days, email email@example.com, or if you prefer to cheer on from the sidelines, you can still do your bit by sponsoring a swimmer via the Swimathon website.