Main Building, in front of the Main Building
22. 3. 2016 – 22. 6. 2016
The Negrelli Viaduct is the second oldest bridge in Prague and the oldest railway bridge over the Vltava. In 2016, we will celebrate the 170th anniversary of the initiation of this illustrious structure. The viaduct begins in Prague 1, New Town, and continues over the Florenc Bus Terminal, forming a border between New Town and Karlín, through Karlín and over Štvanice Island to Holešovice-Bubny. The primary reason for the bridge construction was to connect the railways from the north, Děčín and Dresden, with the only existing station of that time – The State Company Railway Station (today Masaryk Station).
In 1845, the bridge design was drawn up; in September it was reviewed and approved by a committee. The Austrian engineer Alois Negrelli von Moldelbe (1799–1858) took over the bridge construction when the original builder Jan Perner died (1815–1845). The structure, which employed about 3,000 workers, was begun in the spring of 1846 and it opened as early as June 1, 1850. For many years, the bridge had different names. It was referred to as the ‘State Railway Company Viaduct’ or the ‘Karlín Viaduct’. In the 1950s, the bridge finally began to bear the name of its builder – the Negrelli Viaduct.
The Negrelli Viaduct is distinguished by its length of 1,110 m, rather remarkable for the time; yet, it does not include the eastern part on the right-bank head of the bridge which was built later. The bridge is equipped with two railway tracks and is lined with stone railings which are 7.6 m apart. Formerly, Bohemian granite ashlars were used for the spans of the bridge and the piers were panelled with sandstone and granite ashlars at the corners. Freestone, mainly marlstone, was used for the core. The piers are founded on wooden gratings. After the mid-20th century, the unity of the material was severely disrupted because, unlike the original Negrelli structure, the building materials and construction concept of the eastern tracks were not consistent.
The Klein Brothers and Vojtěch Lanna Senior were the structure suppliers. Three spans were demolished in order to build the bridge over Křižíkova Street (1952–1954) and the gap site was spanned with girders made of prestressed concrete. In 1981, a similar action was carried out on the Holešovice side, above the Bubny Embankment. The Negrelli Viaduct survived the worst flood of Prague in 2002 without suffering any damage because the bridge design took into account the 1845 major flood experience.
Despite the criticism of the late 19th and early 20th centuries, claiming that the structure caused an improper disturbance in the Karlín and Holešovice districts, this outstanding mid-19th-century railway bridge is regarded as one of the best in Central Europe.