The Deutschlandticket is primarily designed for unlimited travel on all local and regional public transport throughout Germany; however, it does allow for limited travel into the Czech Republic via specific cross-border routes. You cannot use it for travel deep into the Czech Republic (such as to Prague or Brno), but you can use it on regional trains that cross the border to specific destination stations. For example, you can travel from Dresden to the border town of Schöna and continue on some regional services to Děčín if the service is operated by a German transport association or falls under specific cross-border agreements. It is also valid on certain bus lines that cross the border in the Bavaria-Bohemia region. It is strictly not valid on long-distance EuroCity (EC), InterCity (IC), or high-speed (ICE) trains that travel between the two countries. If you plan to go beyond the immediate border stations, you must purchase a separate Czech rail ticket from the last German station covered by the ticket. Always check the specific "Tariff Provisions" for the regional transport association (like VVO or VGN) that manages the border crossing you intend to use.