I don’t remember seeing so many beer drinking city workers in the movie, but this is the place that was Harry Potter’s access route to Diagon Alley in the Philosopher’s Stone movie. See that blue door? What is an optician today, was the Leaky Cauldron pub in the movie and the entrance to Diagon Alley (Wegisweg for Dutch readers). To be honest, I’m not that good at spotting film locations, but the fact that so many people showed an interest in this shop and were taking pictures of it, kind of gave it away.
Unfortunately I didn’t see any shops that would sell anything on Hogwarts supply list, but then again I’m just a muggle (as far as I know). But even so, Leadenhall Market did feel kind of magical to me, and different from other covered markets I’ve seen in London. It’s open Monday – Friday from 11am to 4pm.