The bell tower, begun in 1173 as the third and final structure of the city’s cathedral complex, was designed to stand 185 feet (56 metres) high and was constructed of white marble. Three of its eight stories had been completed when the uneven settling of the building’s foundations in the soft ground became noticeable. At that time, war broke out between the Italian city-states, and construction was halted for almost a century. This pause allowed the tower’s foundation to settle and likely prevented its early collapse. (source:http://www.confiduss.com/en/jurisdictions/hungary/ )