Cooling system

A cooling system according to an embodiment of the invention is provided, for example, with a container, a housing, a plurality of modules, and an opening. The container has a first wall section which constitutes a floor surface, and a second wall section which intersects the first wall section. The housing is contained in the container and is provided with a plurality of shelves arranged in a first direction extending away from the floor surface. The plurality of modules are supported by the respective shelves, are arranged in a second direction intersecting the first direction and extending along the first wall section, and generate heat. Air for cooling the plurality of modules flows into the container through the opening. An air introduction passage is provided in the housing on the side opposite the second wall section. An air discharge passage is provided between the housing and the second wall section. An intermediate passage extending between the introduction passage and the discharge passage are provided in the housing. The opening is disposed next to the introduction passage in the second direction and extends, when viewed in the second direction, at least between one end section and the other end section of the housing in the first direction.