Even if you have seen it hundreds of times it will still stop you in your tracks. A great piece of architecture and apparently the largest brick structure in Europe.
I love how much you are aware of the changing seasons out of the city; there are numerous beautiful forests around Hertfordshire to go for a run, a walk or have a picnic. One of the best destinations for a day out from London might be Northaw Great Wood. The main entrance is located on the Ridgeway, the B157 from Cuffley to Brookman's Park.
The Princess Louise, was a Victorian Gin Palace, with mirror and tiles galore, segregated seating and extraordinary urinals. With pints of beer just over £2 you're laughing. It gets packed so we come for a lunchtime pint.
A great place to start the day if you are in South London is Federation Coffee in Brixton Village. The food is great and so is the coffee. This is a very chilled place where you can get both and indoor and outdoor experience (even though the whole place is under the Village roof).