The Metro (Underground) network of the Spanish capital (approx. 6. 5 million inhabitants in the urban area) is one of the world's greatest: 13 lines run on a system length of about 300 kilometres.
In addition, there are three tangential lines with a length of almost 30 kilometres, which are operated as a light rail with low floor cars. To avoid the term "Tranvía" (Tram), these routes are called "Metro Ligero" (Light Metro).
Operator of the Underground is → Metro de Madrid S.A.
, for the operation of the light rail the companies "Metros Ligeros de Madrid S.A." (line ML1) and "Metro Ligero Oeste, S.A." (lines ML2 and ML3) were founded.