The Cathedral of Brasília in the capital of the Federative Republic of Brazil, is an expression of the architect Oscar Niemeyer. This concrete-framed hyperboloid structure, seems with its glass roof reaching up, open, to the heavens. On <answer>31 May 1970</answer>, the Cathedral’s structure was finished, and only the 70 m (229.66 ft) diameter of the circular area were visible. Niemeyer's project of Cathedral of Brasília is based in the hyperboloid of revolution which sections are asymmetric. The hyperboloid structure itself is a result of 16 identical assembled concrete columns. These columns, having hyperbolic section and weighing 90 t, represent two hands moving upwards to heaven. The Cathedral was dedicated on <answer>31 May 1970</answer>.
When was the Cathedral of Brasília dedicated?
31 May 1970