Manholes

thumb|Postmaster-General's Department|PMG manholes in a city street, [[Perth, Western Australia]] thumb|Sanitary manhole|Manhole being used to access sewer thumb|Installation of a fiber-optic manhole in Brooklyn, New York thumb|An uncovered manhole in Beirut, Lebanon A manhole (utility hole, maintenance hole, or sewer hole) is an opening to a confined space such as a shaft, utility vault, or large vessel. Manholes, typically protected by a manhole cover, are often used as an access point for an underground public utility, allowing inspection, maintenance, and system upgrades. The majority of u

removable plate over manholes, to prevent things from falling into sewers and other tunnels