The London Underground is a public rapid transit system serving London, England.
The Rotterdam Metro serves as a key component of public transportation in the city.
The Paris Métro is one of the densest networks in the world with 16 lines and over 300 stations.
The Tyne and Wear Metro is an extensive light rail system serving Newcastle, Gateshead, South Tyneside, North Tyneside, and Sunderland.
The Dortmund Stadtbahn is a light rail system that serves the city of Dortmund in North Rhine-Westphalia, Germany.
The Glasgow Subway is the third oldest underground metro system in the world.
The Frankfurt U-Bahn is a rapid transit system serving the city of Frankfurt and the surrounding region.