This may not be much of a secret but deserves a mention. I find it hard to go anywhere near this place without having to go there. Freshly baked Beigels hot salt beef and it never closes, 24 hours a day 7 days a week.
Just above the Dorfman Theatre lobby at the National Theatre, is the entrance to the high-level walkway, a public walkway that overlooks the National Theatre props and scenic workshop.
It's free and is a unique chance to get a glimpse of what happens backstage. I love popping in when I'm on the south bank, as you get a completely different sight each time, depending on which production the workshops are working on at the time.
Relaxed with character. Tiny garden at the back overlooked by Waterloo train station. Not sure if mother cat still lives there. Nice to go with friends or alone. Books. Good for a coffee and cake or a bottle of beer. Spiral staircase down to basement. One loo serves the place - tip - lock the door, don't just rely on the curtain and save an awkward encounter.
Photo credit: http://www.appletoothpaste.co.uk/2017/05/coffee-scooter-caffe-london.html