No, the Eurail Pass is not valid for travel on the Paris Metro (Subway) or the standard city bus network. The Eurail Pass is specifically designed for national and international heavy rail travel between cities, rather than inner-city local transit systems. However, a common point of confusion is the RER (Réseau Express Régional) train system in Paris. Your Eurail Pass is valid on the RER lines, but only on the portions operated by SNCF (the national French railway). This typically includes RER lines B, C, D, and E, but notably excludes the RER A which is primarily RATP-operated. Even then, using a "travel day" on your pass just for an RER trip is usually a poor value, as a standard ticket only costs a few Euros. For the Metro and buses within Paris, you will need to purchase separate tickets (Ticket t+) or a Navigo pass. If you arrive at Gare du Nord or Gare de l'Est via a Eurail-eligible train, you must still buy a separate Metro ticket to reach your final hotel destination within the city center.