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Cassero Senese
Grosseto, Tuscany, Italy
The keep incorporated in the Bastione Fortezza
Cassero Senese
Coordinates	42°45′42″N 11°06′59″E / 42.761756°N 11.116467°E / 42.761756; 11.116467
Type	Keep
Site information
Owner	City of Grosseto
Open to the public	Daily
Condition	Well-preserved or intact
Site history
Built	1345
Built by	Republic of Siena
Materials	Stone

The Cassero Senese (English: Sienese Keep) is a 14th-century fortification located in Grosseto, Tuscany, Italy.

Built by the Republic of Siena, it survived the demolition of the Sienese fortifications ordered by Cosimo I de' Medici, Grand Duke of Tuscany in 1565 and was incorporated in the Bastione Fortezza (Fortress Bastion) of the Grosseto city walls.

• Beranger, Eugenio Maria (1987). Fonti per lo studio delle mura di Grosseto dal 1767 al 1950 (PDF). Rome: Paleani Editore. Archived from the original (PDF) on 2020-03-28. Retrieved 2020-03-28.
• Boschi, Mariano (2014). Grosseto e le sue mura. Ghezzano: Felici Editore.
• Polito, Concetta; Marri, Alessandro; Perin, Luca (1990). Le mura di Grosseto. Rilievi e studi per il recupero. Florence: Alinea Editrice.
• Giorgio Spini (1983). "I Medici e l'organizzazione del territorio". Storia dell'arte italiana. Momenti di architettura. Turin: Giulio Einaudi. pp. 202–207.

Wikimedia Commons has media related to Cassero Senese (Grosseto).

• "Le mura di Grosseto". Retrieved 28 March 2020.