Piombino is an Italian town and comune of circa 35,000 inhabitants in the province of Livorno (Tuscany). It lies on the border between the Ligurian Sea and the Tyrrhenian Sea, in front of Elba Island and at the northern side of Maremma.
- Co-Cathedral of Sant'Antimo (c. 1377), built by the Augustinians and originally dedicated to St. Michael.
- The Rivellino (Walls Tower-Gate), the most ancient monument in the city (1212).
- The Chiesa della Misericordia (early 13th century). It houses a precious 15th century crucifix.
- The Cassero Pisano(Castle). It is formed by two distinct building, the Fortress, built under Cosimo I de' Medici (1552–53), and the Cassero (late 15th century), the latter used as military jail until 1959.
- The Palazzo Comunale (Town Hall), mostly a modern reconstruction of the ancient Palazzo degli Anziani (1435). In the Musters Hall, with portraits of the Princes of Piombino.
- Chapel of St. Anne, a noteworthy Renaissance work by Guardi. Annexed is the Torre Civica (Town Tower, 16th century).
- The Cisterna di Cittadella (Citadel's Cistern), also by Guardi. On the sides are the portraits of Jacopo III Appiani and his son and wife, later disfigured by order of Cesare Borgia.
- Casa delle Bifore (House of the Mullioned Windows, 1280s).
- The Natural Province Reserve Padule Orti Bottagone, created in 1998, next to the locality of Torre del Sale.