Construction of Cologne Cathedral began in 1248.
The foundation stone was laid on 15 August 1248 by Archbishop Konrad von Hochstaden. The new cathedral was planned as a grand Gothic church and as a fitting home for the Shrine of the Three Kings, which had made Cologne an important pilgrimage destination. Its design drew heavily on French Gothic ideas, including the ambitious treatment of the choir.
The eastern arm was completed and consecrated in 1322, allowing worship to begin while construction continued elsewhere. Work slowed and eventually stopped in the late medieval period; the unfinished building remained famous for its enormous crane and incomplete towers.
A major revival began in the 19th century, encouraged by renewed interest in medieval architecture and the rediscovery of the original plans. Construction resumed in 1842, and the cathedral was completed in 1880 according to its medieval design. Thus, 1248 marks the medieval beginning, not the date of final completion.