The oldest public art gallery in London also is my local gallery in my neighbourhood. Opposite to the Dulwich Park where I walked with my puppy regularly. They have great collections of Dutch paintings as well. My husband found the original Dutch painting of the print at his home he was growing up with.
London is blessed with many fine parks, but Brockwell is a real jewel in south London. A short walk or bus ride from Brixton, or right by Herne Hill overground station, the park includes large grassy areas, the fantastic Brockwell Lido (a vast open-air pool – hectic mid-summer unless you get in early - a 7am swim is utterly blissful), tennis courts, a bowling green, a BMX track, a mini-railway, a secret garden, and a few newly landscaped ponds. Perfect for a lazy summer day.