Mentioned by urbanest
The 10 Best Parks in London for a Picnic
"Despite being the home of Winter Wonderland every year, Hyde park is not short on things to do in the summer. Here you can find the Serpentine, London’s oldest boating lake, where you can rent a boat or swim in if the weather allows. As well as that, there’s a rose garden and a meadow if you want some pretty views with your picnic."