Wrocław to Cottbus train with Deutsche Bahn (RB,EC)

Deutsche Bahn (DB) is Germany’s main train operator, running around 40,000 domestic and international services each day. Its fleet includes a variety of train types: high-speed ICE (Intercity Express) trains, reaching up to 300 km/h; IC (Intercity) and EC (EuroCity) trains for long-distance travel; and IRE (Interregio-Express), RE (Regional Express), and RB (Regionalbahn) services for regional and local connections. While bathrooms are standard on all trains, amenities such as onboard restaurants and free Wi-Fi are available only on certain train types and routes. DB offers a wide range of fares, including Super Saver, Saver, and Flexible tickets, along with discount cards like the BahnCard 25, 50, and 100. Additional options include single tickets, day tickets, and group tickets. Popular routes include Berlin–Munich, Hamburg–Frankfurt, Cologne–Stuttgart, Berlin–Dresden, and Hamburg–Cologne, as well as numerous regional services across Germany.

Koleje Dolnośląskie (KD), or Lower Silesian Railways, is a regional rail operator in Poland's Lower Silesian Voivodeship, established in 2007 and fully owned by the local government. KD primarily runs local passenger trains within the Lower Silesian region, with some routes extending into Germany (Görlitz, Dresden, Forst) and the Czech Republic (Liberec, Trutnov, Adršpach). The company offers various ticket types, including standard, discounted, and special offers like the \Dolnośląski Bilet Weekendowy\" and \"EURO-NYSA-TICKET.\" KD's rolling stock includes both diesel and electric multiple units, such as the Newag Impuls. They also accept Polregio tickets on their trains."