The House of Terror was created as a memorial to the victims of Fascism and Communism, and to help explain what happened here during those oppressive regimes. It's inside what was once the headquarters of the Fascist Arrow Cross and then the ÁVH, the Communist secret police. It's a highly interactive museum, and it makes for a chilling experience. This building has seen some of the darkest days of 20th-century Hungary, and its basement cellars, now part of the exhibition, were once used as torture chambers. It's nearly impossible to imagine what so many people went through there. The exhibition itself is mostly in Hungarian, but there are printouts everywhere with English translations. You may want to collect them all and save them for later reading, as there is a lot of material to take in. The English-language audio-guide is a wise investment in order to get the full experience. Note that the museum has been controversial since it opened in 2002. Critics say it places too much blame on the Communists, the Germans, and the Allies (who changed Hungary's borders after World War I). What it is missing, they say, is a deeper look at Hungary's role in the Holocaust. Note that it's probably best to skip this museum if you have young children in tow.