Whitechapel Fatberg Manhole Cover

The lowdown

In 2017 sewer workers beneath Whitechapel discovered a horror that made headlines around the world, a fatberg, a vast solid mass of congealed cooking fat, wet wipes and waste, longer than two football pitches and weighing as much as several buses, blocking the Victorian sewers below.

It took weeks of grim labour with shovels and high-pressure jets to clear, and a piece was even displayed in a museum. To commemorate the battle, a specially designed manhole cover was set into the street above, saluting the crews who keep the city's hidden plumbing flowing. It is free to find, a strangely fitting monument to a very modern and very disgusting London legend.