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.
Not been in many years, but spent a large part of my childhood watching people row and sail back and forth. It freezes over in winter and in February 1893, Jack Selby drove a coach and four horses across the reservoir.
Lots of traditional charming country pubs around the area, but it can a bit hit and miss. A really friendly one with amazing food (and a unusually large veggie selection…) is the Beehive in Epping Green; close to the Great Wood. It's friendly enough you dare going there by yourself with the paper and are not at the mercy of local rubbernecks ("the rubberneck" = person who stares at strangers without any sign of guilt)