Judy May: I have had many holidays in Wales where I have greatly enjoyed swimming outdoors. My favourite place, apart from the sea, is Llyn Gwynant in the valley of Nant Gwynant.
The lake is just off the road and there is a bit of parking space next to it.
I've had some very strange looks from people passing by on the road but the swimming is lovely
Kate Rew: Recommended in Wild Swim by Kate Rew & Dominick Tyler (Guardian Books, £14.99):
Swim rating: Moderate- adventure.
The large grey rock on the far side of Gwynant looks like an elephant, making a swim to it seem an obvious journey. The rock gets the sun in the morning and is good for jumping. (Check depth first – the depth varies from 80ft to shallow below the elephant). Both ends of the lake are very shallow so it gets very warm in summer.
You can enter via the campsite, or park on the beach opposite the rock on the A498, which runs along the south side of the lake and gets the sun all day. The water here is shallow so good for kids, and the rock is about 400 m across from this point - wetsuits (or wetsuited friends/ boat cover) recommended if you are going to commit to this swim: it would be possible to hobble back from the Elephant around the shore if you got cold, but possible to get in to trouble getting cold on the trip. Better, perhaps, to stay warm and safe.
There is a campsite at the end of the lake, from which you can walk up Snowden. www.gwynant.com. Gwynant is a popular lake for kayaking and canoes, and they can be hired by the hour for safety cover.