A manhole cover is a removable plate forming the lid over the opening of a manhole, to prevent anyone or anything from falling in, and to keep out unauthorized persons and material.
They date back at least to the era of ancient Rome, which had sewer grates made from stone.
Read more about Manhole Cover: Description, Circular Shape, Manhole Covers and Race Cars, Propelled Into Space, Other Uses, Gallery
Famous quotes containing the word cover:
“There is nothing more poetic and terrible than the skyscrapers’ battle with the heavens that cover them. Snow, rain, and mist highlight, drench, or conceal the vast towers, but those towers, hostile to mystery and blind to any sort of play, shear off the rain’s tresses and shine their three thousand swords through the soft swan of the fog.”
—Federico García Lorca (1898–1936)