The challenge of building the Buda-Pesth Chain Bridge across the icebound Danube

The freezing of the Danube over the winter months was a critical influence in the provision and method of construction of what is now the Széchenyi Chain Bridge in Budapest, Hungary, between 1839 and 1849. The bridge of boats connection between the former towns of Buda and Pesth could not operate in the winter months and it was imperative that a permanent structure be built. The major considerations in building the bridge related to the dangers posed by the river freezing over: in particular, choosing a chain bridge with the least number of piers and locating it to take account of the dangers of inundation from river ice. In describing the challenges faced and overcome, the paper makes use of a wealth of material from archives in both Budapest and London. These include the original contract for building the cofferdams, the drawings referred to in the contract, British engineer, William Tierney Clark's own comments and correspondence (particularly with his superintendent engineer Adam Clark) and vivid contemporary accounts of the freezing Danube. It is therefore an amalgam of contract history, civil engineering and cultural history.