The Greenwich Observatory with its green laser beam can transfigure any night sky. If you decide to cross the Thames via the foot tunnel, make sure you look out for the green ray. You can be on one side of the meridian in a minute, and cross to the other side on the next, without even realising it.
Free natural ponds, open all year round (check online for varying opening hours according to seasons). Get an absolute get away feeling right in the heart of London, a treat if you enjoy swimming with ducks. Amazing park to enjoy a few games of cards and a walk around afterward too...
Audiophile paradise. Boasting one of the coolest looking and beautifully crafted sound-systems I've ever seen. More listening bar than club, it has a low key vibe with a diverse roaster of talented DJ's spinning an eclectic mix of tunes and full albums.