Crossing the Iron Curtain in an “Ulm Box”

The Danube begins at the confluence of the Breg and Brigach rivers, whose springs are both located in the central Black Forest . It is 2857 km long and today flows through Germany, Austria, Slovakia, Hungary, Croatia, Serbia, Bulgaria, Romania, Republic of Moldova and Ukraine. Before it flows into the Black Sea, it fans out to form the Danube Delta, which is now an ecological reserve.

Ulm is a large city in the east of the German state of Baden-Württemberg, on the border with Bavaria. The university city is located on the Danube at the edge of the Swabian Alb and has about 126,000 inhabitants. It was first mentioned in documents as early as 854. It is the first major city on the course of the Danube.

Vienna (population in 2025: 2,040,914) is the federal capital and the political, cultural, and economic center of Austria. More than one-fifth of the country’s population is concentrated within the city limits, and as much as one-third in the Greater Vienna area. Vienna is of particular historical significance as the capital and, by far, the most important royal seat of the former Habsburg Monarchy. Today, Vienna is home to the headquarters of several important international organizations.

The Kingdom of Hungary (Magyar Királyság) existed in changing borders since the year 1000. Already in the early modern period it fell to the Habsburg Monarchy, in which it later became the most important of the so-called Lands of the Hungarian Crown (also Lands of the Holy Hungarian Crown of St. Stephen or, after 1867, also called the Hungarian half of the Empire). Unlike other Habsburg territories - such as the lands of the Bohemian Crown or the Archduchy of Austria itself - the Kingdom of Hungary never belonged to the Holy Roman Empire.

Budapest (population 2025: 1,676,000) is the capital and largest city in Hungary. It is located in the center of the country, on the Danube. Budapest was formed from the merger of the cities of Buda on the left bank and Pest on the right bank of the Danube. Pest was already the capital of Hungary from the beginning of the 11th century and from the 13th century often alternated in this function with Buda. When the both cities were merged as Pest-Buda during the revolution in Hungary in 1848, they already formed a single entity. After the restoration of the monarchy (from 1526 as part of the Habsburg Monarchy), however, this merger was abolished in 1849 and re-established 1873. In this context the Hungarians replaced the Germans as the majority in the city. After the collapse of the Habsburg Monarchy in 1918, Budapest remained the capital of a now independent Hungary. After Hungary's entry into the Second World War on the side of the German Reich in 1941, most of the city's Jews were ghettoized in 1944 and later deported to concentration camps or murdered. The 1956 popular uprising against Soviet tutelage in Hungary began in Budapest. In connection with the uprising and its suppression, the capital lost around 70,000 people. Today, Budapest is not only the country's largest economic and cultural center, but also one of the most important in East Central Europe.

The People's Republic of Hungary was a socialist state in East Central Europe that existed from 1949 to 1989. The occupation of Hungary by the German Wehrmacht began in 1944, followed by the Red Army, which occupied the entire country in 1945. After the end of the war, attempts to establish a democracy failed and the political system was successively transformed into a one-party system under communist leadership.

The People's Republic of Hungary was a member of the Warsaw Pact and was under the strong political influence of the Soviet Union, which violently suppressed the Hungarian uprising in 1956 with the help of the Warsaw Pact states (except Romania). To appease the population after the wave of reprisals against the participants of the uprising, economic and political reforms were introduced in the 1960s that went beyond the usual restrictions in the Eastern Bloc. In connection with the economic crisis of the late 1980s, further economic reforms and extensive political liberalization as well as opening to the West were gradually introduced, which also heralded the end of the socialist People's Republic. In 1989, the present-day Republic of Hungary was finally proclaimed.

Czechoslovakia was a state existing between 1918 and 1992 with changing borders, names, and political systems. Its territories are now part of the modern-day states of Czechia, Slovakia, and Ukraine (Carpathian Ukraine, occupied by Hungary in 1939 and transferred to the Soviet Union in 1945). After 1945, Czechoslovakia came under increasing political influence from the Soviet Union. After the communist party seized power in 1948, the country finally became part of the so-called Eastern Bloc, a satellite state of the Soviet Union, and a member of the Warsaw Pact from 1955. Between 1960 and 1990, the communist country was officially known as the Czechoslovak Socialist Republic (abbreviated to ČSSR). The democratic political change was initiated in 1989 with the Velvet Revolution and culminated in 1992 with the founding of the independent Czech and Slovak Republics.

Bratislava (population in 2025: 480,902) is located in southwestern Slovakia on the Danube River, which forms the border with Hungary and Austria. Bratislava was first mentioned in 907, although the city is likely much older. It was situated at the crossroads of Slavic, Magyar (Hungarian), and German influences. From the 10th century onward, Bratislava was mainly under Hungarian influence, and from 1536 to 1783 it served as the capital of the Kingdom of Hungary. Since the founding of Czechoslovakia in 1918 until today, Bratislava has been the capital of Slovakia and the most important political, economic, and cultural center of the state, which has been independent since 1993.

Komárom (population in 2024: 19,862) is located in northern Hungary on the Danube. It was founded under the name Új Szőny as a suburb of Szőny, but in 1896 it was incorporated into the town of Komern (Slovak: Komárno), located on the northern bank. After the city center north of the Danube was occupied by troops from the newly established Czechoslovakia, the southern part of the city remained Hungarian under the name Komárom. Szőny was incorporated into Komárom in 1977.

Esztergom (historically: Gran, population in 2024: 28,521) is a city in northern Hungary. It lies directly on the Danube, across from its former suburb, the present-day Slovak city of Štúrovo. Esztergom is one of Hungary’s oldest cities. In the 11th and 12th centuries, it was the country’s capital. The Archidiocese of Esztergom was established in 1002, though its seat was located in Trnava and later Bratislava during the Ottoman rule from 1543 to 1683. Today, automobile manufacturing is the city’s most important economic sector.

Nyergesújfalu (population in 2024: 7,206) is a town in northern Hungary, located directly on the Danube, which forms the border with Slovakia. Its German name, Sattel-Neudorf, was given by Swabian settlers who were resettled there in the mid-18th century by the Habsburg Empress Maria Theresa (1717-1780). They were intended to bring about an economic revival in the region, which had been liberated from Ottoman occupation.

Štúrovo (population in 2025: 9,221) is a city in southern Slovakia. It is also known by its Hungarian name, Párkány. The German name for the city is Gockern. Štúrovo lies on the Danube, which forms the border with Hungary at this point. The town was founded in the 16th century on the site of the village of Kokot, which was destroyed to make way for an Ottoman fortress. After the defeat of the Ottoman army in 1683, the area once again became part of the Habsburg Monarchy. In 1948, the town was renamed from Parkan to Štúrovo in honor of the Slovak writer and philologist Ľudovít Štúr.