underground railway

• Sistema ferroviario que discurre bajo tierra, normalmente en una ciudad, utilizado para el transporte público. En inglés británico se le llama a menudo «underground» o «tube».

A railway system that runs underground, typically in a city, used for public transportation. In British English, it is commonly referred to as the 'underground' or 'tube'.

1. Subway systemA2formalbritish

   An electric railway system that runs mostly in tunnels beneath the ground, used for public transportation in cities.

   metro

   • The London Underground railway is one of the oldest in the world.
   • She takes the underground railway to work every day.
   • The underground railway connects all major parts of the city.

2. B2formalamerican

   A historical secret network used to help enslaved people escape to freedom, especially in the United States before the Civil War.

   ferrocarril subterráneo

   • Harriet Tubman was a famous conductor on the Underground Railroad.
   • The Underground Railway helped thousands of people reach freedom.
   • Many brave individuals risked their lives to operate the Underground Railway.