Generally, the U-Bahn (Untergrundbahn) is NOT included in the Eurail or Interrail pass. Eurail passes are designed for national and international heavy rail networks operated by companies like DB (Deutsche Bahn) in Germany or ÖBB in Austria. Local city transit systems—including U-Bahns, trams, and buses—are managed by municipal authorities (like the BVG in Berlin) and require a separate ticket. However, the S-Bahn (Stadtschnellbahn), which is the suburban rail network, is typically included in your Eurail pass in cities like Munich, Berlin, and Vienna because it is operated by the national railway companies. A common "pro-tip" for 2026 travelers is that while you can use a travel day for an S-Bahn ride, it is often a poor use of value unless you are also taking a long-distance train that same day. For city-only travel, it is much cheaper to buy a local "day ticket" and save your Eurail days for expensive cross-country journeys.