A manhole is an access point to underground utility infrastructure, covered by removable lids typically set into roadways or sidewalks. Manholes provide entry for workers to inspect, maintain, and repair underground systems including sanitary sewers, storm drains, water mains, and telecommunications cables. The covers are usually round because circles cannot fall through their openings regardless of orientation. Municipal public works departments maintain manholes as part of utility infrastructure. Manhole covers sometimes attract collector interest due to unique municipal designs, and some cities have used decorative manhole covers as public art celebrating local history or identity.