Porta Pia

Michelangelo's last architectural work (1561–65), commissioned by Pope Pius IV — a gate that's more sculpture than fortification, with deliberately playful and unusual ornamental details (drooping bunches of fruit, towel-like decoration) that mark a transition toward Mannerism. It's also the site of the 'Breach of Porta Pia' on 20 September 1870, when Italian troops broke through the Aurelian Walls 30 metres to the right of the gate, ending the temporal power of the Pope and unifying Italy.