Underground stations are facilities where trains operate below the ground level, primarily serving urban areas. They are part of a larger public transportation system, often referred to as the subway or metro. These stations typically feature platforms for passengers to board and disembark from trains, along with ticketing areas and sometimes shops or amenities. The design of underground stations varies widely, but they usually include stairways, escalators, and elevators for accessibility. Safety features, such as emergency exits and signage, are also important. Many cities, like London and New York, have extensive underground networks that help reduce traffic congestion and provide efficient travel options.