A manhole is a small tank used to receive, link and distribute underground pipes or conduits; They are usually buried and have a lid on top so they can be searched and cleaned of impurities inside.

They are used in sanitation, drinking water and irrigation networks, and can house the shut-off valves of buried networks. They are also used in electricity distribution networks and other wired services, such as telecommunications.

They are built of brick, plastered and troweled internally with cement mortar. They can also be prefabricated in concrete or plastic materials. Caps are usually made of metal materials such as cast iron "Casting (metallurgy)").

The first meaning provided by the dictionary of the Royal Spanish Academy for manhole is: box or tank to receive water and distribute it.[1]​ Thus prioritizing over any other type of use other than the channeling of fluids. In this sense, the manhole is part of the sewer.

By extension, the one that is part of the buried electrical networks, gas networks, etc. is also called manhole. They are normally recordable and can house the ground connection, shut-off valves or other mechanisms.

As a precursor to the caskets there is the colagón. The colagón was a hole at ground level that, from the kitchens of the houses (in Valladolid), communicated with the street and through which wastewater was discharged. The collagons continued in a tile or wooden channel (equivalent to the current collector) and protruded from the wall more than half a rod. In the century it was mandatory to make drains in the patio or corral and when this space does not exist, it is allowed to open the drain in the street as long as a fountain pipe does not pass through the place.