The Hospital in the Rock, or Sziklakórház as it is called in Hungarian, is a museum today, but once was a functional hospital built inside the hill under Buda Castle in the 1930s, in preparation for World War II. The site can only be visited by guided tour, which is offered every hour in Hungarian and English. Discounted rates are available with the Budapest Card.
The hospital served primarily during the Siege of Budapest in 1944 and 1945. While it was initially designed to treat 70 patients at most, at one point it wound up being used to treat 600 soldiers, with water, food and equipment shortages becoming a real issue and causing many deaths. It was used again in 1956 during the Soviet Revolution and was then repurposed as a nuclear bunker where doctors and nurses could stay safe and help the wounded – hence why the current displays house anti-radiation kits and Soviet spying equipment.
Located near the Szell Kalman Square and Déli Railway stations, the Hospital in the Rock's 60-minute tour costs 4,000 Ft for visitors between the ages of 6 and 25, or 2,000 Ft for seniors between 62 and 70. Family tickets are also available, but the site is not recommended for children under 6. The temperature inside is around 59-64 degrees Fahrenheit (15-18 Celsius) year-round, and photos are not allowed on the tour. The museum is open every day from 10 a.m. until 8 p.m. Buses 16, 16A and 116 can be taken to the Szentháromság Square stop.