Generally, the Eurail Pass cannot be used on subways, metros, or local city buses. The pass is designed for travel on the national railway networks (like SNCF in France or DB in Germany) and specific inter-city or international high-speed lines. For example, you cannot use your Eurail Pass on the London Underground (The Tube), the Paris Métro, or the Rome Metro. However, there is a very important exception: S-Bahn trains in many German and Austrian cities. S-Bahn networks are often operated by the national railway (Deutsche Bahn or ÖBB), and these are included in your Eurail Pass. This is incredibly useful in cities like Berlin or Munich, where the S-Bahn functions like a metro system but covers larger distances. In London, the pass now covers the Elizabeth Line and some London Overground routes, but still not the traditional Underground. In 2026, always check the "Rail Planner" app; if a train is listed there, it's usually covered. Just remember that if you are using a "Flexi Pass," using it for a short city hop on an S-Bahn will "cost" you one of your full travel days, which is rarely a good value unless you are also taking a long-distance train that same day.