An evening at Italy's largest opera house is magical. Although the original 1737 theatre burnt down in 1816, Antonio Niccolini's 19th-century reconstruction is pure Old World opulence. If you can't make it to a performance, consider taking one of the 45-minute guided tours of the venue. Tours usually take in the foyers, elegant main hall and royal box (the best seat in the house) and tour tickets can be purchased at the theatre up to 15 minutes before each tour begins.
Next door, the Palazzo Reale is home to the theatre's museum, MeMus.