Leake Street Tunnel is a 300 metre long tunnel that runs beneath Waterloo Station. Since 2008 it has become decorated for its entire length, including the roof, with street art and graffiti. The tunnel has been designated as free wall space so artists can work here without fear of prosecution. As a result there is a thriving community of artists working here and an ever changing variety of work. It is therefore highly likely there will be something new if you make a return visit.
The tunnel is actually quite close to the London Eye but most of the thousands of visitors it attracts are unlikely to venture across York Road to find the tunnel. I started my visit at Waterloo Station which is served by Jubilee, Northern, Bakerloo and Waterloo & City lines as well as being a mainline station for South Western trains. Leave the station by the steps just to the left of the toilets. At the bottom of the steps its a left turn round onto York Road. From here Leake Street is a short walk on the left. It is well signposted when you get there.
The tunnel is quite dark although there is low level lighting installed to enable you to see the murals. During the day there does seem to be a lot of people around looking at the walls.
There are also a couple of bars at the York Street end of the tunnel. However if may well be a completely different experience visiting after dark. I would recommend a visit during the day when there are lots of people around.