On 20 November 1849 Buda and Pest were joined for the first time by a permanent crossing: the Széchenyi Chain Bridge (Széchenyi lánchíd), a suspension bridge over the Danube in Budapest that links Clark Ádám Square below Buda Castle with Széchenyi Square in Pest. It was the first permanent bridge over the Danube anywhere in Hungary, and its centre span of about 202 metres was then one of the longest in the world. It was designed by the English engineer William Tierney Clark, built under the Scottish engineer Adam Clark (no relation), promoted by Count István Széchenyi and largely financed by the banker Georgios Sinas. Blown up by retreating German troops in January 1945 and rebuilt for its centenary in 1949, the bridge tied Buda and Pest together a generation before the two towns merged into Budapest in 1873.
1820–1832: Ice on the Danube and Széchenyi’s Bridge Society
Before the bridge, Buda and Pest were linked by a pontoon bridge and ferries, and winter ice could cut them off from each other. Its history usually begins in the winter of 1820, when Count István Széchenyi (1791–1860) needed to cross to begin a journey to Vienna, where his father was gravely ill, and was held up by drifting ice. On 4 January 1821 he wrote in his diary that he would give a year's income towards a bridge between Buda and Pest.
He was not the only one thinking about it. In May 1823 the military engineer György Baricz argued in the newspaper Magyar Kurír that a permanent crossing could be hung from iron chains, since stone arches and timber trestles would not survive the Danube's ice. A decade later Széchenyi turned the idea into an organisation: on 10 February 1832 he founded the Bridge Society (Hídegylet), with the Bavarian envoy Baron Eduard Steinlein as president and himself as vice-president. Széchenyi and his friend György Andrássy then toured England to study its bridges. There Thomas Telford recommended a chain suspension bridge, which needs few piers in the riverbed, pointing to his own Menai Bridge of 1826, and Széchenyi saw the work of William Tierney Clark, designer of Hammersmith Bridge and Marlow Bridge over the Thames.
1836–1839: Act XXVI, Georgios Sinas and a Toll for Nobles
The Hungarian Diet ordered the bridge built in Act XXVI of 1836 and set up a 30-member national delegation chaired by Palatine Joseph. When a public appeal for money in January 1837 raised little, Széchenyi turned to Georgios Sinas (1783–1856), an Austrian–Greek banker based in Vienna who had been raised to the Hungarian nobility in 1818. Sinas agreed on 25 February 1837 and formed the Chain Bridge Company. The Vienna banker Salomon Rothschild and the Pest house of Wodianer later took about a third of the shares, Széchenyi 3%, and Sinas covered the rest; his name is still inscribed on the south-western foundation on the Buda side.
Tierney Clark offered three designs and George Rennie four. Two English experts, John Plews and Samuel Slater, advised as few river piers as possible, faultless foundations and a site away from the river's narrowest point. On 18 September 1838 the delegation chose Clark's three-span chain bridge on the line of the Nákó House in Pest, where Gresham Palace stands today. Opponents in the Diet still pushed a Hungarian alternative from the Hoffmann brothers and Károly Maderspach, whose longest span would have been only 114 metres, but Széchenyi carried the vote. The contract, ratified on 14 May 1839 and enacted as Act XXXIX of 1840, granted the company tolls for 87 years and banned any other bridge within a mile. Every user would pay, nobles included, a quiet blow against the tax exemption of the Hungarian aristocracy.
1840–1848: Timber Piles, Mauthausen Granite and Iron Shipped from England
Tierney Clark could not stay in Hungary, so construction was run by Adam Clark (1811–1866), an Edinburgh-born engineer who had first come to Pest in 1834 to supervise a dredger Széchenyi had ordered for the Danube. The first pile was driven at the Buda pier on 28 July 1840. Piling took two years and employed up to 800 men at a time, alongside about 60 families of English mechanics and ironworkers; Adam Clark travelled to Slavonia and the Tyrol to choose timber for the roughly 5,000 piles, which were cut from pine. Coffer dams of triple pile rows were pumped dry so the piers could be founded on firm ground, and the foundation stone was laid at the Pest abutment on 24 August 1842. The piers were faced with granite from Mauthausen in Austria.
Most of the ironwork came from Britain; the cast-iron cross-girders were cast at Andrássy's Dernő works. Hunter & English supplied the anchorage shoes and cast-iron chain saddles, and Howard & Ravenhill the hangers, chain plates and wind bracing; altogether 2,146 tonnes of iron went into the bridge. The first shipment left on 2 October 1846 and travelled by water, through the canal linking the Main to the Danube that King Ludwig I of Bavaria had built in that decade. The chains were assembled on floating scaffolds and hauled to the tops of the piers by a steam engine on the bank. The first chain end was fixed in the Pest anchorage on 28 March 1848. Eleven of the twelve lifts went smoothly, but during the last, in July 1848, a link in the hoisting tackle snapped. The chain crashed onto the scaffold, onlookers including Széchenyi were thrown into the Danube, one worker was killed, and recovering the chain cost four weeks.
1848–1849: A Half-Built Bridge in the Hungarian Revolution
The final stages coincided with the Hungarian Revolution of 1848. Adam Clark sympathised with the revolutionaries but refused a crowd's demand to dismiss his foreign workers. On 1 January 1849 the carriage of Sámuel Bónis, on Lajos Kossuth's orders, carried the Holy Crown of Hungary across the unfinished bridge on its way to Debrecen. Days later, as the Austrian army took the twin towns, some 70,000 soldiers and hundreds of guns crossed on planks laid over the cross-girders.
Both armies then tried to wreck it. When Austrian troops prepared to blow up the bridge in spring 1849, Clark flooded the anchorage chambers and broke the pumps so the chains could not be dislodged; on 21 May a gunpowder charge damaged eight cross-girders and killed the officer in charge, Colonel Alnoch, but left the bridge standing. Weeks later Clark persuaded the Hungarian commander, General Henryk Dembiński, that the deck could simply be dismantled rather than burned. The bridge was formally opened on 20 November 1849 in the grim weeks after the revolution's defeat, under the military rule of Julius Haynau. Széchenyi never crossed it: by then he had withdrawn to an asylum at Döbling near Vienna.
1849–1913: Tolls, Marschalkó’s Lions and the Birth of Budapest
Tolls began at once: 1 krajcár for a pedestrian, 3 for someone driving a cow, 10 for a large cart. In 1852 the four stone lions by the sculptor János Marschalkó were set on the abutments, and a popular Budapest legend says they have no tongues. The tongues are there, but they cannot be seen from street level. Adam Clark stayed on, married Mária Áldásy in 1855 and built the Buda Castle Tunnel, begun in 1853, which emerges directly opposite the bridge. He died in 1866 and lies in Kerepesi Cemetery.
Toll income peaked in 1871 at 723,462 forints, but the state had already bought the bridge from Sinas's son Simon under Act XXX of 1870, cutting the 87-year concession to about 20. In 1873 Buda, Pest and Óbuda were merged into Budapest, the union the bridge had anticipated. Margaret Bridge opened in 1876 and took much of the heavy traffic. Around the bridge's 50th anniversary at the turn of the century it formally took Széchenyi's name, and in 1912 the square at its Buda end was named Clark Ádám tér; the Zero Kilometre Stone, the point from which Hungary's road distances are measured, stands there.
1914–1945: Rebuilt in Steel, Then Blown Up in the Siege
By the early 1900s the deck swayed badly under heavier traffic, and engineers decided to replace the whole ironwork while keeping the stone piers and the bridge's outline. It closed on 3 February 1914. On 30 June 1914 a boathouse broke loose from Margaret Island, smashed through the scaffolding of the Buda span and swept 74 prepared chain plates into the Danube; only 15 were recovered. The rebuilt bridge, with carbon-steel chains half as large again in cross-section and stiffening girders replacing the old timber trusses, reopened on 27 November 1915. Its metalwork now weighed 5,194 tonnes.
On 28 October 1918, during the Aster Revolution, police fired on demonstrators marching across the bridge towards Buda Castle, killing three or four in what became known as the Battle of the Chain Bridge. Weeks later, from 1 December 1918, the Károlyi government abolished the tolls on all of Budapest's bridges.
Its worst day came during the Siege of Budapest. On 18 January 1945, as German forces withdrew from Pest to Buda, they blew up the Danube bridges still standing, the Chain Bridge and Elisabeth Bridge last of all. Only the charges on the Pest side detonated, but the chains tore free of their anchorage and the deck fell into the river, leaving just the two stone towers standing.
1947–2023: The Centenary Reopening and the Car-Free Bridge
The decision to rebuild came in spring 1947, backed by donations from across Hungary and abroad. Floating cranes lifted the wreckage, and tests showed the steel was sound: 76% of the old chains could be reused, with 590 tonnes of new links forged to match. The portal arches of the towers were widened so two buses could pass, and the carriageway through them grew from 5.4 to 6.45 metres. The bridge reopened on 20 November 1949, exactly 100 years after its first opening.
Later work kept it going: a 1973 overhaul replaced nearly a tenth of its 100,000 rivets, a full renovation of the bridge and the Castle Tunnel ran from 1986 to 1988, and in 1996 the communist-era coats of arms on the towers gave way to the restored national arms. The last renovation, contracted to A-Híd in 2021 for 18.8 billion forints, closed the bridge for more than two years; it reopened to pedestrians on 4 August 2023, and private cars are no longer allowed across. The bridge appears on the 200-forint coin, and in 2001 the Hungarian pilot Péter Besenyei flew under it upside down. To see it in its city, read our guide to Budapest, the capital of Hungary; to follow the river it spans, see the Danube River guide, or compare it with other crossings in our list of famous bridges in the world.