The Thames Barrier, with its striking stainless steel sails, was an iconic construction project, completed in 1984. It is the second largest movable barrier in the world, and protects central London against tidal flooding. It is raised increasingly often to protect London against high tides.
Besides looking at the barrier itself, visitors can pay a modest fee to go inside a small information centre (Thurs-Sun) which contains an interesting exhibition. When I visited, the viewpoint café above it was shut, but there was a temporary one across the car park. If you go, don’t miss the exhibition. When I lived in London the Barrier was under construction, but I never went to have a look.
Visitors can reach the site by walking to Unity Way from the A206 along a dismal industrial road, or through a small park. There is a pay and display car park on site.