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.

I rediscovered this place recently having not been for years and now I keep returning. The geological galleries are my favourites.

best family run sushi i can find in London.  Not flashy but that not the point.  Its a small honest run place.  Its great.

Eccentric and surprising house and museum of architect Sir John Soane. Mostly unchanged since his death over 180 years ago, it is full of atmosphere. Also have spotlit, late night openings.  

There are three branches of this South Indian Vegetarian Restaurants across London, two in the West End. They all look pretty unremarkable from the outside, the décor is pretty basic, but don't be fooled - the food is wonderful! It's incredibly cheap and the friendly staff cater for vegans and people with food intolerances really well.