The Gleno Dam in Valle di Scalve, Italy, was built between 1916 and 1923, and collapsed on December 1, 1923, just two months after its completion, killing at least 356 people. Source.
Chiesa di Sant'Adriano al Foro Romano, as painted by Achille Pinelli in 1834. The building housed the Roman Senate from the 40s BC until about 600 AD. Source.