The design of the two high-rise towers for the Donau-City in Vienna by Dominique Perrault Architecture represents the concluding phase of a development extending over several decades: on what was originally a municipal rubbish tip the UNO-City was erected (1973–1979), tentative plans to hold the 1995 Vienna-Budapest EXPO here were soon abandoned, as a result architects Krischanitz and Neumann (commissioned by WED AG) produced an urban design masterplan for the area in 1992. The outcome is an entirely new urban district with a diverse range of functions.