Warm summer nights should be spent in the high grass in Hampstead Heath above the ponds. For midsummer bring herring, snaps and songs and stay until sunrise!
I go to the Heath every weekend (often via the wonderful Waterlow Park which skirts Highgate Cemetery) and during the week too if I’m working from home; it helps to put things in perspective when I’m thinking about my work. It’s great in the summer for obvious reasons but I love it the most in autumn and on those rare days it snows so much London grinds to a halt (which doesn’t take much). Everyone heads up there to make giant snowballs/cats/creatures and surf down Parliament Hill on anything they can get their hands on. Grown ups turn into kids for the day. My husband and I made this snow yeti last year, it was sad to leave him behind but he soon made friends and even made it into the Camden New Journal.
By far the best bagels in London, they are open 24 hours and being just down the road from my flat a bit too local. It is run by a man called Mr Sammy, who doesn't muck about with portion size. It is well worth a visit especially for their smoked salmon and cream cheese speciality.