From the Telegraph:
Golden gate: Masterpiece restored
No less an artist than Michelangelo said it was so beautiful it could grace the entrance to Heaven and dubbed it the Gate of Paradise.
But after six centuries exposed to the elements, the Renaissance Porta del Paradiso in Florence's main piazza had lost its lustre and was removed in 1990.
Now the landmark has been returned to its original glory by a restoration that took 33 years and involved the use of lasers and chemical baths to remove centuries of grime and oxidisation.
The gold-plated Porta del Paradiso, as it is known in Italian, was created by Lorenzo Ghiberti after he was commissioned by a guild of Florentine cloth importers.
Ghiberti, a renowned sculptor and metalworker, took 27 years to complete the work and included a bald-headed likeness of himself in the doors, which were finally unveiled in 1452.