If you want a peaceful day out of the busy city, Highgate doesn't really feel like London. The cemetery is interesting and peaceful, there's a tour of the old half which is definitely worth the money. Karl Marx, among others are buried there.
A special place, a shop which is like a museum, worth popping in to feel the humanness and heritage of London. And if you are looking for rope, compass or any sailing supplies, this is the place. There is no shop like it.
Beautiful museum with permanent collections on anthropology, natural history and musical instruments. Surrounded by a park with farm animals and beautiful views of London skyline.
London has great green spaces. There are large royal parks and small public gardens, hidden allotments and roof terraces. Each one has its own identity and characteristics and everyone has their favourite. In summer they become extensions of people homes, you see girls sunbathing from 9 am and the endless picnics mean you can eat 3 meals a day in the park. My favourites - St James Piccadilly Gardens, Hyde Park, Barbican Conservatory.