Not the most exciting place inside, but a lovely rooftop area which not all that many people seem to know about, 2 mins walk from Old St station. If it’s packed then The Red Lion is just up the road.
There are many great parks in London to choose from, but Hampstead Heath is by far my favourite; a lido, Parliament Hill with a great view of the city, ponds, woods and plenty of space. It’s a great place to hang out in the summer, but also presents a lovely walk in the winter. Address: (As it’s so big obviously it doesn’t really have a specific address but there are 2 main entrances) Entrances by Gospel Oak or Hampstead Heath Entrance.
Spacious bar and dining place with a scandinavian feeling to it. Different independent shops like record shops, flowers, etc inside the place. Pizza is good!
Although my skating days are now over, Stockwell Skatepark located just behind Brixton Academy is one of the reasons I moved to Brixton. It’s an excellent place, lumpy and hectic but totally friendly with decent Portuguese coffee and cakes just next door.