Begin your day by visiting the Hungarian National Museum, which houses a vast collection of Hungarian art and artifacts. Next, head to the Hungarian State Opera House, a stunning neo-Renaissance building that hosts world-class performances. In the afternoon, visit the House of Terror, a museum that documents the atrocities committed by the fascist and communist regimes in Hungary. End your day by taking a sunset cruise along the Danube River, which offers breathtaking views of the city's landmarks.