Abandoned buildings in london?

Please bear in mind that abandoned buildings are generally private property and usually have some kind of security system or guards to stop you from going in and exploring. I'd encourage you to seek proper permission from the owners to gain access rather than just climbing over the fence and sneaking in through an unsecured door. These places, especially if they've been empty for a long time, may be in a poor state of repair and have weak floors or other structural hazards, may contain things that you'd rather not come into contact with, like asbestos or discarded hypodermic needles, or even be occupied by squatters or other undesirables. If you just stroll into one like you're out on a picnic then things may not end well.

The creepiest building in London is the Houses of Parliament, Westminster, SW1. Alas the building is not yet abandoned

Aldwych Tube station - you can't go in without permission though. Essex Road station not abandoned but hasn't been done up in decades lots of creepy passages

St Clements was an old psychiatric hospital which is now closed down on Mile End Road.

Queen Elizabeth Childrens Hospital, Hackney Road, E2 just past Hackney City Farm.